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  • How does a 2-Stroke Engine work?

    Just how does a 2-stroke engine work? Hopefully this will help:


    Click on the image







  • How To - Adjust The Timing



    How To - Adjust The Timing

    Topic:                           Adjust Wetbike Timing

    Expertise Required:      Minimal

    Estimated Time:            1 Hour

    Parts Neeed:                 None 

    Tools Needed:               You will need the following tools:

          • Hand-impact for stator screws
          • 3lb Hammer
          • Flashlight

    Step-By-Step:               Here's how to get it done


    The ignition system consists of no moving parts. The ignition timing should hav to be set once and then remain unchanged unless the stator position is moved or an ignition component is changed.


    1. Connect a timing light to the engine.


    2. Start the engine and run the engine at 1,000 rpm. At this engine speed, timing mark B must align with mark A on the magneto case.


    3. If the timing marks align as mentioned, timing is correct. If the marks do not align, loosen the two screws securing the stator plate and rotate stator in the correct direction. If an unstable timing is indicated by the timing light, a faulty PEI unit might be indicated.


    4. Tighten the screws and check ignition timing


      Timing Advance                Position


      1000 rpm                          8deg BTDC


      5000 rpm                         25deg BTDC


    Be sure to check accuracy of tachometer if unexplained variations in timing are being observed.


  • How To - Airbag Front Suspension



    How Do I . . . Airbag Front Suspension Setup 

    Topic:                          Front Bumper - how did this come about? That is, how did the wetbike community come upon this design? I'll post what I remember, but would like others to fill in the stuff I've forgotten (most of it really).

    A Little Background

    A few years ago a thread was started about how we could do something to decrease the violent impact of the front ski when landing off of jumps and/or riding in choppy water. I don't know if that thread still exists, but for quite a while it was one of the main topics on wetbike.net.

    There were even some outstanding discussions using the online chat. We had tons of people throwing out ideas and asking "what if".

    The Discussions

    These discussions covered a lot of ground. Some of the things thrown out were:

    • Spring assembly inside steering tube
    • Mounting motorcycle-style forks on wetbike
    • Gas-pressurized shocks - like the ones on suv rear-hatches
    • Compression-only setup - how to get around rebound slowness (would hold ski up too long)
    • Airbag front end - and how to make it work
    After several months, the real issues narrowed down to 2 things. First of all was to dampen just the last couple of inches of travel (to eliminate the slamming effect) - and the second was to not affect the rebound (so that the ski could fall down without any friction.

    My Airbag Prototype

    I got fixated on the idea that an airbag setup would be the shnizzle. Spent time looking at several airbags - and how they could be mounted. Even planned on "bleeding" off some compression from the top cylinder to provide pressure for the bag. Too complicated.

    Anyway, I did figure out how to crate a new lower H-Beam assembly that could cradle an airbag and allow it to pivot and not tear itself to pieces. Here's a few pics:

    I was just about to get a prototype welded up when a much better design came along.

    The Winner

    The design with the round bumper has turned out be the best so far. It's simple, inexpensive, easily serviced and durable - a winner all around. The airbag design never made it out of the prototype stage . . . yet 






    Copyright 2011 Capt'n Obveeus

  • How To - BIG BORE Motor (86mm and up)


    How Do I . . . Build a Big BORE Motor? (86mm or larger)

    Expertise Required, Planning, Estimated Time, Parts Needed, Tools Needed, Step-By-Step, Break-In Procedures

    Topic:                          What does it take to build a big bore motor? It takes the following:

        • Proper Planning - parts, machining, consumables, etc.
        • Fairly decent technical skills
        • A good machine shop you trust
        • Basic (metric) hand tools
        • Patience . . . lots of patience
        • Money . . . if your planning says you need $1000.000 - plan on having $2000 available.

    Expertise Required:      Better than average level. Besides the ability to disassemble and reassemble an engine, you'll need to have the ability to do the following:

        • Use the proper tools to be able to measure the port timing for your motor
        • Setup and use a Degree Wheelproperly
        • Accurately measure the ports on your motor (width and height)
        • Accurately measure the piston you are using - and - the NEW BIG BORE PISTONS you plan to use

    Planning:                    You will need to plan the following correctly:

        • How much power do want to make?
        • How much money do you want to spend?
        • What octane of fuel do you want to run?
        • Are you capable of doing this project . . . seriously?
        • Do you have a machine shop that you can trust to bore and deck block?
        • Do you have a machine shop that can modify your cylinder head properly?
        • Oversize pistons - Are you gonna use off-of-the-shelf Wiseco or Tohatsu pistons? Are you sure they're still available in the size you want?
        • Head Gasket - You gonna have a stock one modified, or have a custom one made? If custom, will you with fiber or copper (copper requires much better block/head surface preparation and very rigid installation procedures.
        • Crankshaft Rebuild - Plan on having the guys tig weld the pins and weld in a plug in the lower wheel

    Estimated Time:            My experience has shown that the time needed is as follows:

        • Planning the parts needed, sourcing the parts and getting them ordered (4 hours)
        • Removing cylinder head, setting-up Degree Wheel (1 hour)
        • Measuring the port timings for all of the ports (1 hour)
        • Measuring deck height for both cylinders (about 5 minutes)
        • Disassembling motor, cleaning bores, and doing a port tracing (about an hour)
        • Putting all of the information gathered into a spreadsheet style of format (1 hour)
        • Accurately measuring new pistons (squish band, dome height, pin height, pin boss width, etc) (30 min)
        • Getting crankshaft cleaned and boxed up with new parts to send off to Northern Crankshafts (1 hr)
        • Initial block cleaning after coming back from machine shop (1 hour)
        • Porting - basic cleaning to get aluminum to match liner (1 hour). If having to raise/modify ports, plan on a minimum of (4 hours)
        • Polishing Cylinder Head Domes (about 1 hour)
        • Prepping block for paint (1 hour)
        • Painting block and head (including primer) (2 hours)
        • Measuring and correcting ring end gap (30 min.)
        • Trial assembly (without rings) to verify proper deck height and port timing (1 to 2 hours)
        • Final Assembly of Short Block (1 hour)
        • Trial fit of head (measuring squish with solder) (aboug 1/2 hour)
        • Cylinder head installation (about 30 min.)

    Parts Needed:               Plan on the following minimum parts list:

        • Crankshaft parts - rods, lower bearings, lower pins, all bearings and center seal
        • Pistons - New Wiseco or Tohatsu pistons
        • Piston Pins - New Suzuki pins (the thin-walled shiny ones)
        • C-clips - New Wiseco, Suzuki, or Tohatsu ones. Never re-use old clips
        • Seals - New Suzuki Upper, Lower, and Crankshaft seals
        • Gaskets - New Suzuki Magneto Housing Gasket, Carburetor Gaskets, Fuel Pump Gasket, and Air Box Gaskets
        • Head Gasket - Use a modified Suzuki 60hp gasket or custom-made one of your choosing. Note: You will need to be dead-nuts sure of the gasket's thickness (when torqued) in order to know how much to machine the block and/or head.
        • Cylinder Head - Modified properly to achieve the proper squish band - AND - the proper volume.

    Tools Needed:               Besides the standard metric hand tools, you will need the following:

        • Degree Wheel
        • Digital Dial Indicator that's long enough to reach down in the bores to the piston top at BDC
        • Caliper or equivalent that will help you measure the port shapes
        • Dykem Blue (or equivalent) to mark ports for adjustment/correction
        • Porting (cleanup only)- Dremel with right-angle attachment,beaucoup grinding stones for steel, various burrs for aluminum. 3M style buffing stars for polishing.
        • Porting (real deal) - Flexible shaft porting tool with long shanks and tons of attachments (lots of mooluh)
        • Consumables - WD40, Aerosol Brake Cleaner or Berryman's B-12 (carb cleaner), White Cotton Rags
        • Hand-Impact Driver - for countersunk magneto base screws and magneto screws

    Step-By-Step:               Perform and record all measurements first (during teardown). Then you can do the following:

        • Crankshaft - box it up with all of the new parts and send it off to Northern Crankshafts
        • Once you have recorded all port timings, you can then decide what changes need to be made (decking block, porting, squish band changes, etc)
        • Pistons - once you have yours in your hand (and have measured them correctly), you will know if you need to deck the block (and how much), you will know if you need to adjust port timings, and you will know how much you need to modify the cylinder head.
        • Perform all of your porting cleanup and/or modifications prior to having the block machined
        • Degrease the block and head and get them cleaned-up and ready for machine shop
        • Get your machining instructions together and take parts to the machine shop
        • While you're waiting to get the block/heads back, take the time to degrease, debur, and clean up all of the fasteners. I don't recommend bead-blasting them, but a rotary tumbler works pretty good.
        • When block gets back, prep it good - and immediately oil down the cylinders
        • Piston Rings - Set the end gap properly (a ring end gap grinder works great)
        • First Trial Fit - Assemble pistons onto rods, throw a couple of o-rings on the pistons and drop the crank in (carefully) and button up the bottom end with a few bolts. Don't tighten them down over a couple of ft lbs - just enough to make sure the crank is held in place firmly. Rotate engine around and measure all of the port heights (from the deck) to make sure they're where you want them.
        • More Port work - If you need to make some adjustments at this point, be vewwy careful not to nick the cylinder anywhere with the porting tool. Also be aware that a full de-greasing/wash will be necessary when you are done.
        • Final Assembly - Carefully install the rings, install the 2 new seals in the lower seal housing, grease-up the lower main seal and get your 1211 ready.
        • Carefully lower pistons into bore and set crankshaft bearings down into the saddles. Be careful to get get center seal lip oriented correctly - and - make sure the bearing alignment pins are in their correct spot. Note: On 88mm motors you need to be extra careful when sliding into their bores because the sharp edge of the cylinder sleeves are exposed (if you counter bored the bottom correctly). Sometimes a little screwdriver helps here - but be careful not to snap a ring off.
        • Slide a couple of pieces of wood under block so that pistons won't hit table and spin motor to make sure it turns freely. Tilt up bottom end of the crank and install main seal.
        • Slide on the lower seal holder - make sure you get the little tang on the correct side. Look and the mating surface of the engine housing and you'll see which side it should go on
        • Apply 1211 (case sealer) put the lower engine half on and torque down properly (per service manual)
        • Roll motor over and put a little oil (either 2-stroke oil or 2-stroke engine fogging oil) on the cylinder walls
        • Clean both the block surface and the cylinder head surface thoroughly, install the head gasket and torque down (per the service manual)
        • Prep it for paint - and paint it
        • Run a tap through all mounting holes if they were painted over (coil mount, fuel pump, starter bracket, etc.
        • Install new seal into magneto cover, fill it with waterproof grease, grab a new gasket and install flywheel cover using a hand-impact to set the countersunk screws correctly.


    Break In Procedures:     Opinions vary but here's the method I've used sucessfully:

        • Fuel - double-up on the oil mixture for the first 5 gallons
        • Jetting - if you've built a Hogzilla, then you need to be conservative on the jetting until you get it dialled in. I like to start at either 165 or 162.5 jets for break in.
        • Timing - for break in I like to have the mark in the middle of the hole.
        • First Start - I like to fire it up on the trailer and run it for about 30 seconds or so until I feel some heat building in the block/head. Shut it down and let garage clear out the HUGE SMOKE CLOUD
        • After block cools back to room temperature, I like to do that one more time.
        • Once I get to the lake, I like to run the motor on the trailer for about 2 or 3 minutes until it feels like there's pretty good heat in the motor. Shut it down and let it cool back down for about 5 minutes.
        • Off the trailer and ready for the first ride. It is extremely important to let motor warm up properly before putting any kind of load on it.
        • Idle out from the boat ramp for about 2 or 3 minutes until the motor is starting to get some heat in it. Now, add about half throttle to get the bike moving pretty good - but do not come up onto plane. Keep it there for about 15 seconds, then let it drop back down to idle speed. I do this about 3 or 4 more times on BIG BORE motors with FORGED pistons.
        • Now I roll the throttle on (not full throttle) to get bike up on plane and slow motor back down just enough to stay on plane. After about 30 seconds, I drop back to idle (for cooldown). I'll do this barely-on-plane procedure about 5 or 6 more times - with additional idle around time too. Head to the beack and let it cool down completely (ending first major heat cycle)
        • Out for another ride - after proper warmup again. Same thing on getting up to plane except I increase the speed to about 1/2 throttle (or around 4000 rpm I think). At this time I determine whether the carbs need to be sync'd. If the motor will idle way down without dropping a cylinder, then they're spot on. After about 20 minutes or so of riding, I let things cool down again.
        • Final break in rides - I continue with the long warmups (proper warmups) and constantly vary the speed of the motor. Eventually I do a couple of full-throttle bursts - holding it wide open for about 5 seconds - then slowing back down to an idle. I'll do about 5 or 6 more WOT bursts and then drop down to idle for a half minute or so.
        • Once I've burned about 4 1/2 gallons, then I'll try going WOT for 10 or 15 seconds - then back down to idling around for cool off.
        • Once 5 gallons of the double-oil is done, I'll drop 5 gallons of 91 or 92 octane with 50:1 mixture in there and continue with the short WOT bursts. After burning about a gallon, I'll pull the plugs and see what they look like. Usually I like to burn this additional 5 gallons before doing any jetting changes.


    Simple eh? 



    Copyright 2012 Capt'n Obveeus

  • How To - Blueprint that pump


    How To - Blueprint that Pump, Impeller, and Stator/Nozzle

    Parts Needed, Tools Needed, Step-By-Step, Notes

    Topic:                           Blueprinting pump assembly - hints provided by Wbbrian

    Expertise Required:      Minimal

    Estimated Time:            2 Hours

    Parts Neeed:                 None - unless you are replacing the wear wring, impeller, nozzle bushing or shaft seal

    Tools Needed:               You will need the following tools:

    • 14mm wrench or socket (with long extension)
    • Big MO crescent wrench (12 in or longer) - to hold pump shaft
    • Another Big MO crescent wrench to remove impeller
    • Large Flat File - and wire brush to clean it out with
    • Small die grinder with 3m type of pad
    • Metric tap for ski mounting bolts
    • Mapp Gas propane torch - for stubborn fasteners
    • Razor knife (box cutter)
    • 4 inch grinder with flap wheel (optional)

    Step-By-Step:               Here's how to get it done

    • Remove the pump/ski from the bike - it will save you hours. Before you do, reach in and see if there's excessive play in the shaft (that would allow the impeller to contact the wear ring). It might be time to replace the nozzle bushing and seal.
    • Remove the ski and cleanup the mating surfaces and run a tap through the holes. If you pump looks like this, then it's been loose for way to long.
    • Remove the nozzle (take off the insert step-by-step procedures> 
    • Remove the impeller - stick one of the Big MO's through the pump intake and place firmly on the flats on the shaft (to hold it still). Place the other Big MO on the impeller and remove - TURNING CLOCKWISE (it's a lefthand thread)
    • Remove the wear ring - if you didn't remove the ski, then you'll need to remove some of the studs. Double-nut them and carefully back them out
    • Inspect all parts and decide if the impeller and wear ring are useable (this one is NOT ). New, tight-fitting parts will give best performance. Skat Trak 11/13 impeller will give best holeshot and midrange
    • Pump - take a few minutes to smooth out the inner surface. If you look close, then you'll see all kinds of casting flash - and - a very rough texture overall. If you polish it, cool. But you'll get the same result if you just paint it (smooth surface) - Black Epoxy works pretty good. And . . . you should install a speed plug.
    • Impeller - Clean up (sharpen) the leading edges. If you're up to it, polish that baby
    • Wear Ring - not a whole lot you can do here really. If there's a groove in it, replace it. If you are short of cash - add a couple of space washers onto the shaft to space the impeller back a bit. If your bike is pre-1985, be careful that the impeller won't bottom out against the nozzle. Make sure you have the knocks and o-rings. Replace them if they're all used up.
    • Nozzle - take the time to dress up the edges of the veins and remove any boogers that are on the inside surface of the stator. Here's an example. Also, see if you can smooth-out the inside of the cone after the stator. Every little bit helps. If your nozzle looks like this, it's time to get it welded up or just replaced. Now is the perfect time to replace the bushing and seal if needed. Remember that this seal goes in backwards (spring seal is FACING out)
    • Change the oil in the pump now. Then you can clean everything up and prepare for reassembly.
    • Clean all surfaces thoroughly - the wear ring mating surface - and - the ski mounting surface.
    • Install the impeller (remember that dab of anti-seize). No need to try to tighten it too much - it'll tighten up the minute it's run in the water
    • Install the wear ring and nozzle. I use a small dab of Black Silicone around the edge to prevent any pressure loss
    • Install the ski - look here for the particulars
    • After the 5200 cures, take the time to clean any excess off. Flip ski/pump over so that you are looking at the bottom of the ski. Take a razor knife and remove an excess 5200. Look close to see if the lip of the pump is sticking up above the surface of the ski. Take a 4 inch grinder and level things out. Then, take your rat-tail file and smooth out the front lip of the intake (to remove any sharp edges
    • Reinstall your modified scoop with 5200. Use a dab of it on the bolts - keeps them from falling out. Note - be sure you have run a tap through the holes all of the way to the bottom - and - use compressed air to blow holes clear.


    Saltwater use dictates that all raw aluminum surface need protection. Not so necessary on the impeller but very necessary for the pump and nozzle inner surfaces. Here's some of Wbbrian's work

    Impellers can be tough to get off. Don't use a powertool and try to cut them off - you'll ruin the shaft. Use a Torch and put some heat on it first.

    Always use some anti-seize when installing the impeller.



    Copyright 2012 Capt'n Obveeus

  • How To - Broken Bolt Extraction


    How To - Broken Bolt Extraction

    Parts Needed, Tools Needed, Step-By-Step, Notes

    Topic:                           How do you remove/repair broken bolts and studs?

    Expertise Required:      Intermediate to Expert

    Estimated Time:            Really depends on the repair. Can be as quick as 1/2 hour or longer than an hour for the stubborn ones

    Parts Neeed:               You will need the following parts:

    Tools Needed:             You will need the following tools:

        • Center Punch
        • Drill
        • Small Drill Bits
        • Left-Handed drill extractors
        • Mapp Gas Torch

    Step-By-Step:             Here's step-by-step instructions on how to get it done:

            • If it is sticking up at all, tig weld a nut onto the end of it. The heat will shock things a bit and help the bolt break free
            • If that option isn't available, do your best to grind end flush
            • Take super-extra-care and use the center punch to get a punch in the exact center (or as close as you can)
            • Drill a tiny pilot hole all of the way through - taking care not to break off this pilot drill bit.
            • Step up through different drill sizes until you come to the one you use for the broken bolt extractor you are using.

            • Grab the torch and heat the holy hell out of it and then try to remove it.
            • Most of the time, the heat will help guarantee success. 



    Most of the time, the heat will help guarantee success. However, when that doesn't work then you need to press ahead an install a TimeSert. How To - Thread Repair

    Here's some other pics in this category:




    Copyright 2011 Capt'n Obveeus

  • How To - Carburetor Adjustment


    How To - Adjust That Carburetor

    Topic:                           Carburetor Low Speed adjustment

    Low Speed Range          600-650 rpm
    Pilot Air Screw               1-3/4 turns out 

    Expertise Required:      Minimal

    Estimated Time:            1 Hour

    Parts Neeed:                 None 

    Tools Needed:               You will need the following tools:

          • Large/Short Flat Blade Screwdriver
          • Rope or strap to hold bike to pier (500lb strength minimum)

    Step-By-Step:               Here's how to get it done

    WARNING - DO NOT stand in front of or to the rear of the Wetbike during this procedure. Keep hands, feet and clothing clear of water intake and water outlet area to prevent contact with the moving parts of the Wetbike or contact from objects ejected from the pump.

    CAUTION - Low speed adjustment must be made with an adequately warmed-up engine.

    1. Anchor the Wetbike to a strong pier or piling. Use a 500 pound minimum rating rope or cable. Use the tow rope hook on the rear of the Wetbike. Make sure Wetbike is in at least 3 feet of water (Not Pictured.)

    2. Rotate the pilot air screws clockwise until lightly seated; then back screws out 1-3/4 turns for initial setting. (Not pictured) CAUTION - DO NOT overtighten pilot air screw. Damage to the screw or carburetor body may result.

    3. Start the engine. Hold throttle open slightly as engine is supposed to stop when throttle is released. (Not pictured.)

    NOTE: Engine must be warmed-up. Timing must be correct.

    4. Rotate the air screw until engine runs smoothly and has clean throttle response. (Not pictured.)

    5. Synchronize the two carburetors using a commercial digital, dial or stick-type carburetor balancer (Not pictured.)

    CAUTION - Carburetor balancing is mandatory after the engine carburetors have been disassembled or removed.

    6. Disconnect balance tube from upper carburetor; then connect the balancer to the engine fittings (Not pictured.)

    7. Start engine and set air screw for 1000 rpm. Set the balance guage. (Not pictured.)

    NOTE: Be sure lower inlet hose is plugged.

    8. Disconnect balancer hose from upper cylinder. Connect one of the remaining hoses to the upper cylinder. Zero the balancer. This is done to synchronize balancer. (Not pictured.)

    9. Connect one balancer hose to each of the cylinders. (Not pictured.)

    10. With the engine running, note the positions or settings of the balancer. Both cylinders must be adjusted equally. (Not pictured.)

    11. If the readings are different, rotate the throttle rod adjuster until readings are identical. Lock throttle rod by tightening jam nut. (Not pictured.)

    12. Set throttle for proper operation by rotating air speed screw counterclockwise until engine stops. This setting will let the engine stop, should a spill occur. When restarting Wetbike, it will be necessary to rotate throttle slightly to the slow speed range. (Not pictured.)

    13. Start engine. Quickly release throttle. Engine must stop! (Not pictured.)

    WARNING - Throttle adjustment must be made so engine stops when throttle grip is released. This will allow Wetbike to stop and remain upright if a spill occurs. The operator can then mount Wetbike safely without worry of any rotating components. Failure to correctly adjust Wetbike throttle control may result in personal injury.

    14. Remove the balancer hoses from the balance tube fittings. Install the engine balance hose. Secure with hose clamps. (Not pictured.)


  • How To - Choosing an Impeller


    How To - Choosing an Impeller

    Choosing an ImpellerImpeller Choices, Stock 50hp, Stock 60hp, Added Scoop & Speed Plug, Heavily Modified

    Topic:                           How do you choose the right impeller?

    Expertise Required:      Jedi Master

    Choosing An Impeller:  Which one is best for you? Good question . . . let's consider the following questions:

        • Do you have a 50hp bike or a 60hp bike?
        • How much do you weigh?
        • Do you have a scoop?
        • Do you have a speed plug?
        • Do you have any other mods (exhaust spacer, engine mods, etc)
        • Do you have a new wear ring?
        • Is your nozzle bushing in good shape?

    With the above considered, then here's what I recommend (and note that others have their opinions that differ from mine)

    Impeller Choices:           Here are the impellers that I know of - there might be more

        • Aluminum - stock STRAIGHT BLADE
        • Aluminum - stock CLIPPED EAR
        • Aluminum - used on Seaflash/Jetstars (never seen one but heard of them)
        • Stainless - SKAT TRAK 11/13 (used for stock bikes)
        • Stainless - SKAT TRAK 12/15 (big motor, lots of power required)
        • Stainless - 4 blade used on Seaflash/Jetstars
        • Stainless - 5 blade used on Seaflash/Jetstart
        • Bronze - Straight 13 degree

    Stock 50hp:                  If you have a stock 50hp, then either the stock straight-blade aluminum or the clipped-ear impeller is a good choice. Here's a few things to make sure you're performance stays acceptable.

        • Wear ring - make sure it's a good one with no grooving or nicks
        • Impeller nicks should be ground down and smoothed out
        • Sharpen the leading edges of the impeller blades a little. Don't go crazy
        • Make sure the nozzle bushing is in good shape.
        • Adding a super-scoop is a good addition as long as you DON'T put in a speed plug too.
        • Adding a speed plug works good too - but modify the scoop like this

    Stock 60hp:                   The aluminum clipped-ear impeller seems to be the best overall choice for this bike. The Skat-Trak stainless 11/13 is also a good replacement.


        • The skat trak will lose a mph or two on the top end, but has much better holeshot and midrange over stock. Many wetbikers agree that it's a good tradeoff.
        • Scoops - the Super Scoop works BEST without a speed plug, or works GOOD with a speed plug if modified, and the Ultra Scoop works best with a speed plug. The Pro Scoop works best with a speed plug.

    Added Scoop - AND - Speed Plug:

                   Which scoop is which? . . . look here

                   If you have a speed plug (aluminum or fiberglass) then your choices should boil down to the following:

        • Aluminum clipped-ear - really good top end, good overall performance
        • Stainless Skat Trak 11/13 - excellent holeshot, and midrange
        • Bronze 13 degree straight pitch - little slower holeshot, but best top end

    Heavily Modified

        • The trend here seems to favor the BRONZE 13 degree prop. Watercross of Texas even used to re-pitch these but I don't know what they final pitch was.
        • Since those bronze ones are hard to find, the Skat Trak 12/15 is another good choice.


        1. Running either of the above requires the nozzle bushing and shaft to be in good condition. Any wear/play there will quickly destroy the wear ring.
        2. Both of the above will probably require adding shims so that the leading edges of the impellers don't contact the pump casting.



  • How To - Clean Those Carburetors



    How To - Clean Those Wetbike Carburetors 

    Parts Needed, Tools Needed, Step-By-Step, Adjustments

    Topic:                           Cleaning and setting carbs

    Expertise Required:      Moderate

    Estimated Time:            Depends. If in the bike about 1 1/2 hours. If you pull the motor, about an hour.

    Parts Needed:             Carburetor Cleaner (Aerosol) - Berryman's B12 or equiv.

    Tools Needed:             Here's what I use:

    • 6mm and 8mm open-end for throttle linkage
      • Small Crescent works just as good
    • 10mm wrench for throttle cable (unless someone put an 11mm on there in the past) and emulsion tube
    • 10mm socket, 3 inch extension and ratchet
    • 12mm wrench for carburetor nuts (unless someone put 13mm ones on there in the past)
      • 12mm "shortie" - if you try to pull carbs with motor in the hull
    • 14mm wrench for pump nuts
    • Screwdriver - Flat Blade for hose clamps
    • Pipe Cleaners - the kind with the little plastic bits in them


    Step-By-Step:               Carbs can be pulled in the bike or after the motor is pulled (much easier)

    Begin by disconnecting the battery

    (motor in the hull)

    • Disconnect the fuel line from the tank
    • Remove the dialectic shield
    • Disconnect fuel lines from the carburetors and let them drain
    • Remove all of the carburetor mounting nuts (will need shortie for right-side nuts)
    • Slide choke solenoid back and move it clear
    • Slide carbs off of the manifold - be careful not to kink cable
    • Remove throttle cable
    • (jump to cleanup phase) 

    (motor pulled and on work table)

    • Remove the dialectic shield
    • Disconnect fuel lines from the carburetors and let them drain
    • Drain carbs (on 60hp bikes)
    • Remove all of the carburetor mounting nuts (will need shortie for right-side nuts)
    • Slide choke solenoid back and move it clear
    • Slide carbs off of the manifold and place on work table
    • (jump to cleanup phase) 

    Cleanup Phase - one at a time

    • Start with the lower carb and remove the 4 screws holding float bowl on - note the upper carbs has brackets on it. You may have to "rap" it a bit with a screwdriver handle to get it to dislodge. Be careful, could be full of funk, green corrosion,cocaine-looking stuff or just plain syrup
      • Carefully pull float pin and set the float, the pin and the needle aside. Be sure the little red gasket is in good shape.
      • Take a 10mm socket wrench and remove the seat. Be careful that you don't manhandle things and break the float pin towers.
      • Take a flatblade screwdrive and remove the jet - being careful not to let things slip or booger up the jet.
      • Now remove the nozzle (emulsion tube) - the thing the jet was screwed into. Be careful here - there may be lots of junk holding it in there. Go slow and use carb cleaner to get it out.
      • Remove the pilot air jet on top of carb, then remove the idle-air screw (in the throat of the carb).
      • Begin cleaning the carb body - using the pipe cleaner to get through the top passage and the front passage for the idle-air mixture.
        • Get everything clean enough so that you can see right through the carb with no debris visible.
        • Take special care to run the pipe cleaner through the intake nipple and passage way. 
      • Clean the car bowl. Might require you to let some cleaner soak in there a while to break things loose.
      • Clean up the nozzle. This thing is perhaps the most important and needs to be spotless and all of the tiny holes need to be clear.
      • Cleanup the jet - but don't do anything that might alter the hole size and/or shape of either side of the hole
      • Take some carb cleaner spray and make sure the pilot jet is clear. You should be able to see through the holes from one side to the other. Note: They are NOT DRILLED through from the bottom.


    • Install the pilot jet into the top and tighten (not gorilla tight)
    • Install the idle-air screw and spring and tighten down until lightly seated. Then unscrew it 1 3/4 turns.
    • Install the nozzle (emulsion tube) and tighten. Then install the jet and tighten down - being careful not to booger up the end.
    • Install the seat - being sure the little red gasket is there - and tighten thoroughly. Be careful not to let tool swing around and mess up float towers.
    • Grab the Seat assembly, put it on the float and install the assembly (sliding the pin into place).
    • Adjust the float so that it sits level when you hold carb up with bowl surface level. Bend tab that needle sits on to get proper adjustment.
    • Put clean bowl on and re-install all screws (and brackets).

     Do the same with the upper carb and reinstall. 

    Adjustments:                        There's very little to adjust on these carbs.

    • The idle-air mixture should be set initially to 1-3/4 turns out initially (lake testing may reveal that slight adjustments can be made to this setting).
    • The other adjustment concerns the synchronization of the carbs. That procedure is here


    Copyright 2012 Capt'n Obveeus

  • How To - Cure Loose Ski Braces

    [sigplus] Critical error: Image gallery folder wetbike/ski_related is expected to be a path relative to the image base folder specified in the back-end.


    How To - Cure Loose Ski Braces

    Parts Needed, Tools Needed, Step-By-Step, Notes

    Topic:                           If you let your ski braces get loose, they'll "work" themselves into the fiberglass. 

    Expertise Required:      Beginner, Intermediate, Expert, Jedi

    Estimated Time:            <honest time estimate - 1/2 hr increments>

    Parts Neeed:               You will need the following parts:

        • 5200
        • Acetone
        • White Cotton Rag

    Tools Needed:             You will need the following tools:

        • Metric socket (13mm?) and either a flat blade screwdriver of metric allen
        • 14mm wrenches to loosen front pump bolts so that brace(s) can be removed

    Step-By-Step:              It's a good practice to place a nice pad of 5200 under these things. Here's how you apply this cure:

        • You man have either a single (WETCO) brace or the 2-piece "bowlegged" style.
        • Loosen the rear mounting nuts (on the pump studs) so that the brace(s) can be removed
        • Remove the front 2 mounting bolts on each side and set brace(s) aside
        • Take some Acetone and clean fiberglass of thoroughly
        • Lay a nice pad of 5200 down where the feet contact the ski (on each side) - don't make it more than about 1/8 thick though - the thicker it is, the more cleanup you'll have to do.
        • Let it sit for about an hour
        • Take the acetone and clean the bottoms of the brace(s)
        • Put a couple of bolts through the brace(s) and carefully reinstall it/them
        • While it's sitting there, slide the nuts onto the pump studs up far enough that the brace just touches the pump
        • Put the rest of the front bolts in the braces
        • Now - PAY ATTENTION HERE - tighten these 4 nuts just enough that you see the brace start to squirt out some 5200
        • Let that sit for about 4 days and then remove the front 4 bolts and get all of the old 5200 off of them. Apply a dab of fresh 5200 and reinstall them and tighten down
        • Tighten down the front pump nuts - and double-nut them if you haven't already

    Note:                         The dab of 5200 on the bolts will help keep them from ever vibrating out.







    Copyright 2011 Capt'n Obveeus

  • How To - Cure Porpoising


    How To - Cure That Porpoising Wetbike

    Parts Needed, Tools Needed, Step-By-Step, What Is Your Bike Doing?, Bad Yoga, Let's Look Closer, Doin' The Dirty, The Last Resort 

    Topic:                           Porpoising - What is it and how do you cure it?

    Expertise Required:      Beginner 

    Estimated Time:            Well, it just depends on what you find during the inspection phase 

    Parts Needed:               You will need the following parts:

        •  Rear Ski (worst case scenario)
        • Couple of washers (easy fix)
        • 1/2 tube of 5200 - to re-glue ski and skeg
        • Creeper or piece of cardboard to lay on if your bike is on trailer 

     Tools Needed:             You will need the following tools: 

        • Finely tuned CE's (calibrated Eyeballs)
        • Allen Head socket to remove scoop and/or skeg
        • Screwdriver and small wrench to remove skeg hardware (if needed)
        • All of the tools required to remove ski/pump assembly (if you need to re-glue that ski). See the technical article for ski removal/replacement

    Step-By-Step:            First of all, you need to be able to identify it correctly - then you can choose a plan of action. You also need to understand that there are just some bikes out there that are more prone to this than others (fiberglass bikes more so than Metton).

    What Is Your Wetbike Doing?:  It is important to diagnose the behavior correctly. That is, if your bike only starts to porpoise right at full speed, you could be experiencing over-stuffing of the pump. Not very common, but it has happened. If your ski is in excellent shape, this might be you - and you'll need to modify your scoop (see tech article).

    However, if your bike porpoises all of the time - it's time to dig in deeper.

    Identify The Bad Yoga:   If you have an older bike (50hp or fiberglass hull), the odds are that your rear ski is abused/shot. If it looks bent lika a banana, it's probably gonna porpoise. If you have a super scoop on it (big double-bladed red one) and you see daylight between the ski and the two front tips, it's definately bent. Example:

    The best solution at this point is 2-pronged. First, fab up a 1/4" spacer to go between the forward brace (round brace or H-shaped one with 2 rubber donuts). This will help hold the front of the ski down and reduce flexing. NOTE: The rubber bumpers should always be in contact with the hull while at rest.

    If you have a bike that has the H-Beam style of brace (Says WETCO) on the top (where you can't see it - wtf?) - then you need to inspect the ski from the bolt holes all of the way back to see if it is cracked. If you have cracks from the wear-ring to the back (on each side of the skeg) it's probably game-over for that ski.

    Now That Things Are Straightened Out: 

    OK, your ski looks good and you've got the front supports setup properly . . . and it porpoises a lot, the next area to look at is the Hull Seal. With bike sitting stationary (on trailer or the boat ramp), put your foot on the front of the ski and lift up on the hull. If you have a buddy - float bike out into waist-deep water and try it again. If you see your motor rocking back and forth - time for a new hull seal. They are still available - and/or the ones for a Mercury Sportjet are an excellent option - especially if your bike has been reinforced and the hull thickness is not stock. The Grommet P/N's are:

    1/4" 25-820663-250 3/8" 25-820663-375 1/2" 25-820663-500

    If everything looks/feels fairly firm, it's onto the next thing . . .

    Doin' The Dirty:             OK, it's time to pull the ski off of the pump and re-seal the ski (see tech article). Tech - Ski Removal and Replacement

    The Last Resort:            So, you've done all of the above and it still porpoises. More than likely, the ski is flexing (internal cracks and old age) and there's not a whole lot you can do about it. One last thing to try is to loosen that 2 rear screws holding the skeg on and slip a washer in there (one each side) and tighten it back down. What you are doing is making it like a trim tab. Some folks have had success with this - and with 2 or 3 washers too. Others, not so much.


    If that didn't do it, it's definitely time for another ski !





    Copyright 2011 Capt'n Obveeus

  • How To - Degreeing an Engine


    How To - Degreeing a Wetbike Engine 

    Expertise Required, Estimated Time, Parts Needed, Tools Needed, Step-By-Step, Pics

    Topic:                           If you are going to check/verify/modify the PORT TIMING, then you must Degree your motor.

    Expertise Required:      If you are rebuilding your motor, then you can do this

    Estimated Time:            About an hour to do a thorough job. Getting setup takes about 10 minutes, and measuring/recording the results take the remainder.

    Parts Needed:               Degree wheel kit. I used this one.

    Tools Needed:               Crescent wrench to turn flywheel nut.

    Step-By-Step:               Read the instructions for your degree wheel kit

    • Install wheel onto crankshaft and tighten nut finger tight
    • Figure good location to get pointer installed correctly (fuel pump or coil mount boss)
    • Figure out how to mount dial indicator securely
    • Get your wheel set so that you can verify TDC (top dead center) and BDC (bottom dead center)
    • Rotate engine around so that you can see exhaust port start to open (record degrees of rotation)
    • Do the same for the main, aux, and the boost ports. Note that the boost ports open at a different time than the mains and aux (by design)
    • Use a caliper to also measure the distance from the top of the deck to the roof of all of the ports (record these)
    • Rotate motor to BDC and measure the height again. This will give you the size of the ports (port opening) accurately
    • Use these measurements to create a plan-of-action for porting

    Pics:                             Here's a few pics I took a while back


    Copyright 2012 Capt'n Obveeus

  • How To - Eliminate Drunken Horse - Front Suspension Service


    How To - Front Suspension Service (no more "drunken horse")

    Parts Needed, Tools Needed, Before You Begin, A Little Bakground, Why Was That Important?, Dive In, Look Carefully, Can I just Add Nylons?, Inspect Rear Mounts, What Do I Do Now?, Take a Break, Final Assembly, Care and Feeding

    Topic:                           So your wetbike has been handling like a "drunken horse" lately and you want to diagnose it and fix it properly.

    Expertise Required:      Intermediate

    Estimated Time:            Couple of hours tops

    Parts Neeed:               You will need the following parts:

        • Full set of Nylons (8 total)
        • Full set of Sleeves (8 total)
        • New Nylok nuts (as needed)

    Tools Needed:             You will need the following tools:

        • Metric wrench to take the bolts loose
        • Small hammer to drive bushings in or out
        • 4 inch angle grinder to grind sleeves flush

    Before You Begin:         There are lots of things that work in combination to make a "sloppy" front end. There's the nylon bushings, the stainless sleeves, the bolts and/or stud (depending on year model) and the steering pole itself. All of these can have minor or significant wear - but luckily everything is fixable.

    So, the object of this tech article is to fix any-and-all things that'll tighten up the front end and let it have a long service life.

    A Little Background       There are several styles of steering tube and fastener systems you need to be aware of prior to removal of your system.

    The old 50hp bikes had a steering tube that large bolts threaded directly into. Worked pretty good, but you gotta check those bolts occasionally. This generation also had a Bolt-n-Nut setup on the other end of the beams. You have to check these occasionally too.

    The next generation had the steering tube drilled-through and used long bolts - a better design.

    Then came the advent of the double-ended-stud through the steering tube. It also had NYLOCK nuts on both ends. Much better.

    Somewhere in time, the rear connectins were changed-over to a double-ended stud as well. In addition, there was a sleeve that went in the middle to help prevent over-tightening. The best design so far. About this same time, the ski foot went from a 4-bolt to a 6-bolt design - and a noticeable bulge was added to the outside edge of the casting (both sides).

    Why Was That Important To Know?

    Since all of these designs have wear in different places, it's important to know what your are looking at. If possible it is best to upgrade to the latest-and-greatest design, but that' s lot of work on the older styles.

    With that in mind, I'll walk you through some common ways to fix your steering.

    Dive In:                        Get that baby up in the air and make sure it's stable. Wetbikes are top heavy, so be careful. Have that friend stand by just in case.

    Look Carefully:                  Now that you've got it in the air and you can move ski up-and-down through the full range, it's time to take a close look. Dust off that calibrated-eyeball and look at the following:

    a. How much gap is there between the H-beams and the steering tube?

    b. When you move the ski side-to-side (while holding the steering tube with other hand) - can you see where the slack is. Look close - you should see wear/slack in the bushings, but you might also see lots of slop in the rear end of the H-Beam too. Remember these areas for later reference. If you see a lot of slop, plan on replacing the H-beams too.

    Go ahead and pull the bolts/studs on the upper arm and let the ski fall away. Be aware that you might have to take screwdriver and get these things apart. The reason for that will be made clear in a few minutes.

    Now, go ahead and drop the bottom bolts/stud so that the ski can now be removed and placed on a suitable workbench.

    Look very closely at the steering tube for excessive wear. That is, look to see if the stainless bushings have been "working their way" into the aluminum. Hopefully not, but probably so.

    Can I Just Add Nylons Or Steels?

    If you wanna go cheap, just replace the nylons. Go ahead and buy another set too - they won't last more than a year. Why? If you look at the steel bushings that come out you'll see that they are crushed/deformed (usually on one end or the other). When you put these back in with new nylons, they just wear through quickly and you're back to the same sloppy front end.


    Inspect The Rear Mounts On The Foot:

    Inspect all 4 mount points looking for the same type of damage the steering tube might have (bushings working their way into the aluminum).

    What Do I Do Now?        If you have the old style (where the bolts thread into the steering tube and/or ski foot) then you can only do so much. It's not worth it to have the aluminum welded-up, so you have to use a workaround (outlined in the final assembly step). This workaround is THIN STAINLESS FENDER WASHERS. Take one of the Bolts and get some that just barely slide over the bolt's shoulder.

    Note: If you have bolts that are fully threaded, go ahead and scrap them and get the kind with the proper shoulder on them. The fully-threaded ones don't make a good fit for the Stainless Bushings. You are trying to eliminate slop remember? Also, if your ski foot is drilled through, the fully-threaded bolts will eat into the aluminum. Bad.

    If you have the newer stud-style setup, there's a couple of things you can do to bring it back to better-than-new condition. Here's the steps:

    Step 1 - Go fish out those old, worn-out bushings you threw in the trash, or keep in your spares pile.

    Step 2 - Take drill bit that's slightly smaller than the OD of the bushings and counterbore the holes in the steering tube. Drill to a depth of about 3/4 the length of the Stainless Bushing you are gonna insert.

    Step 3 - Carefully pound-in a used steel bushing. Carefully - If it starts to squish too much, pull it out and go up one size on the drill and try again. Once it bottoms out, take a 4-inch grinder and grind it down almost flush. Measure the inside dimension of one of the H-Beams and make this ever-so-slightly-narrower.

    Step 4 - After you get all 4 installed and ground down, take the drill and ream out the holes. Use a size that's barely bigger than the diameter of the stud. If you go too big, you'll be sloppy again.

    Step 5 - Do the same procedure on the rear mounts (the ski foot).

    The idea is that you want to tighten-up the hole to keep the stud from moving around. As a bonus, you now will have a Stainless-to-Stainless connection - NO MORE DIGGING INTO THE ALUMINUM.

    Take A Break And Run To The Store:

    Throw one of the studs in your pocket and run to the local hardware store (Lowes, Home Depot, Tru Value, etc). You want to look for some THIN STAINLESS FENDER WASHERS. These are your secret weapon. Grab about a dozen or so. You want to size them so that they just barely slide over the stud. OD should be about 3/4" I think.

    Final Assembly:             Ok - I am gonna list the steps I use - you might try things in a different order, but this is what works for me.

    Step 1 - Take a minute and apply a minute amount of waterproof grease on the nylons and Stainless Bushings. Why? Simple . . . it makes things more interesting when you're assembling things.

    Step 2 - Install the rear bushings and sleeves in one of the H-Beams. Then slide the beam into the ski foot - lower holes. If older style, install a bolt on one side (without nut) then the other side. Check for side-to-side movement. If your foot is damaged on both sides, put at lease 1 THIN STAINLESS FENDER WASHER on each. Shim as necessary to eliminate play - but not so tight that it starts to bind. Tighten down the bolts and then install the upper H-Beam the same way.

    If you have the newer style with the long stud and center sleeve - do the same procedure and shim if necessary.

    At this point, you are ready to move from the workbench back to the bike.

    Step 3 - Carry entire ski/foot assembly back over to wetbike and position carefully. It might help to lower the bike slightly at this point. Install the Bushings/Sleeves from the outside into the lower beam and do a trial fit - checking for clearance on each side. Shim if necessary and/or if you have the old style (threaded hole).

    Step 4 -Continue on to the top beam and repeat the process. Keep in mind that for alignment purposes you might not have the same number of shims on each side as you did on the bottom beam. That's OK as long as the H-Beams are parallel and there is no binding when articulating through the full range of motion. Any misalignment binding will lead to premature wear.

    Step 5 - Tightening the fasteners. Care should be taken here. You want to tighten the bolts, but not so tight that you crush the Stainless Bushings. If possible use NEW NYLOCK NUTS and you should be just fine.

    Care And Feeding:          Check the fasteners occasionally and you should be OK. If for some reason you used brass washers, you can watch them corrode - and then plan the next service.





    Copyright 2011 Capt'n Obveeus

  • How To - Engine Rebuild (quickie)


    How To - Engine Rebuild (quickie)

    Parts Needed, Tools Needed, Where Do You Start?, Inspection Cleanup And Prep., Reassembly, Break-In, That First 50:1 Mix

    Topic:                           More Commonly known as a Re-Ring. Even replacing the seals is optional.

    Expertise Required:      Intermediate

    Estimated Time:            About 2 hours - assuming you have the engine removed from your wetbike, seaflash, or jetstar


    Parts Neeed:               You will need some (but not necessarily all) of the following parts:

        • Base Gasket (hard to find),
        • Intake Manifold Gaskets (50hp)
        • Magneto Base Gasket
        • Carb Gaskets
        • New Magneto Cover Seal
        • New lower Seal (big one)
        • New lower seal(s) in the aluminum housing
        • and inner crankshaft seal (60hp)
        • The CORRECT PISTON RINGS. Suzuki used 2 different sizes - be sure you have the right ones beforehand.
      • Shop Supplies: Carb Cleaner (Berrymans B-12), shop rags, clean cotton rags, oil drain pan, 1211, Yamabond, or equiv. 

    Tools Needed:             You will need the following tools:

        • 10, 12 and 14mm wrenches, 14mm socket, Large Socket for Flywheel Nut, Hand-Impact Set, Allen wrench socket for 1 bolt on 60hp bottom end, spark plug wrench, Torque Wrench

    Power Tools: Ball or Stone Hone for cylinder walls, Flywheel removal tool (heavy one), 1/2 in. Air Impact 

    Where Do You Start?:       Let's do the following:

    1. Remove all of the electrical components
    2. Remove the flywheel nut and use puller to remove flywheel
    3. Use Hand-Impact and remove the Phillips Head Screws holding magneto on. Before you get it too loose, note the position of the timing mark. Take a picture if you can.
    4. Now use Hand-Impact and remove the screws holding magneto cover on. If you are careful, you won't need to replace that gasket
    5. Take Carbs and Fuel pump off as an assembly (take fuel pump off first) and drain bowls into oil drain pan. Then take the intake manifold and reeds off. On a 50hp you might tear the gaskets and will need new ones at assembly time.
    6. Take the coil, control unit (60hp) and the rest of the electrical stuff off
    7. Use a 14mm socket and break all of the bottom engine bolts loose. If this is a 60hp, remove the 1 10mm headed bolt down by the seal and the large GOLD allen-headed bolt inside.
    8. Remove the spark pugs and roll engine over onto the head (bottom up)
    9. Remove the rest of the bolts and pull them out (notice the different lengths) then bend the voltage regulator bracket out of the way (60hp)
    10. Dear God, be careful here. Suzuki did not de-burr any of the engines, so all of the edges are ultra-sharp. Wear gloves, or take a few minutes to de-burr the block and the lower half. Also be aware that on 60hp motors you'll see an area in one of the bearing bosses that just like a razor blade. Be careful.
    11. Tap the lower block half loose and carefully set it aside.
    12. Place a nice-clean rag down on the table and lift crankshaft out and place on table. Note: Be careful on 60hp engines as the upper bearing is a 2-piece design. If it falls off and hits the floor it ain't a quickie rebuild anymore. You'll need a new bearing - and someone who can press of the old inner biearing and press a new one on. Also - remove the C-Rings if you can and set them aside.
    13. Get your hone ready, get it lubed up good and run it in from the bottom of the motor. Be careful not to bottom out too hard against the head (remember you didn't remove it). Cycle up and down enough to break the glaze good

    Inspection, Cleanup and Prep:   At this point you need to look at a couple of things that could be show-stoppers. Inspect the piston skirts closely. If you see any cracks, it's game over. You either have a sloppy bore or a twisted crankshaft (or both)

    Also, look to see if any of the bearing alignment pins are missing. If they are - look to see if they are embedded in the top of the pistons and/or in the head. This isn't catastrophic, but if you see damage in either area, you need to look and see if any of the pieces did any damage to the edge of the pistons and/or ring lands.

    Finally, take a look and see if they rings are stick or are trying to stick a little anywhere. If there's a tight spot, it'll be a problem area later, you you might dodge the grim reaper for a while.

    Note: If your bearings look like someone attacked them with a chisel, that's called "brinelling" and it's not great. Not fatal, but you might need to use some Loctite bearing strength sealant on the bearing shell at assembly time.


    Clean block with parts washer, or whatever de-greaser you have. Get everything really degreased. Use a toilet brush and run it though the cylinder bores lots of times. If you have a smaller bristle brush, run it through all of the intake ports too. Don't forget to degrease the lower half of the block and the bolts.

    Then, rinse both the block and the lower half in Hot Water and DAWN DISHWASHING LIQUID. Not any other brand. Don't argue. Have some kind of oil ready to wipe down the bores with. I use 2-stroke fogging oil - works great.

    Rinse parts thoroughly and use compressed air to blow everything dry. You need to put some oil on those cylinder walls within the first minute or 2 after removing from the DAWN. They will rust that fast. Seriously - only 1 or 2 minutes. Be prepared!


    Remove the old seals from the holder and press in new ones while the block is drying thoroughly. Also, remove the old rings from the pistons. BE CAREFUL - they can be quite sharp. Put the new rings on the pistons and get them lined-up correctly. Use a tap and go through all of the large 10mm threads (main bolts). Then take compressed air and blow them clean.

    If there is any residual 1211 or assembly sealant, be sure to get it all off now - and use Acetone or something to get gasket surfaces ultra-clean.

    Take a minute to lube-up the pistons with the new rings. A little fogging oil works good here - or 2-cycle oil. Then install the bearing C-rings back into the block. Make sure they seat correctly.

    Take all of the seals and pack them full of waterproof grease - being sure to make sure the center lips are greased good.

    Bolts - take the time to get them ultra clean and chase the threads if possible. If you don't have a tap-and-die set that fits this thread, use a wire brush and get the bolt threads ultra-clean.

    Reassembly:                Get those hands wiped clean, make sure the block is ready to receive it's new parts and . . . go. While the crank is laying on it's clean are, double-check that the rings are aligned with the alignment pins. Then let's go:

    1. Carefully lift up the crank (watch that upper bearing) and lower it into place. A little wiggling usually helps get the rings to pop into place. If it won't go - don't force it and risk breaking a ring. If you know they're lined-up right, you can use a little screwdriver to help them go (BE CAREFUL IF YOU DO THIS).
    2. Before you get near bottoming out, make sure the alignment pins are in the right place - and that the center seal is lined up with the C-Rings. If your bearings and saddles were attacked by the chisel ninja, now's a good time to apply the loctite to the saddles and bearings.
    3. Finish lowering the crank a little - then slip on the lower main seal and the aluminum seal holder.
    4. With all of the pins aligned, the center seal aligned, and the lower seals and holder in place - slide crankshaft all of the way down
    5. Now, get all of the alignment pins aligned, all of the bearing loctite smeared on, and the mating surfaces cleaned one last time
    6. Apply a tiny amount of 1200, Yamabond, or equiv. to the engine block. Use your finger and make sure it's just enough to "wet" the surface. Put a similar tiny layer on the mating half.
    7. Pick the lower block half on and tap it in place over the alignment pins making sure it lays down flat.
    8. Begin installing the bolts - making sure to dip, spray, or drip oil onto the threads. 2-stroke or fogging oil works good here too. If on a 60hp, don't forget about the bracket that holds the voltage regulator.
    9. Draw all of the bolts down hand-tight. and make sure you see 1211 oozing out slightly all around the mating surfaces.
    10. Grab your torque wrench and set it to 15lbs and torque all bolts (including hex on 60hp motors) in a criss-cross pattern (see service manual for procedure).
    11. Adjust torque wrench to 20lbs and hit all of them again (no bouncing on a torque wrench - just a stready pull)
    12. Set wrench for 25 and make another pass
    13. Set wrench for 29 and make a final pass
    14. Install the reeds and manifold (resist the temptation to use RTV here). No RTV on roller-bearing engines is the rule. 1211, Yamabond and specific Case Sealants are the exception.
    15. Install upper seal (if you are using a new one) into magneto cover, and install. Use hand impact to "set" screws to get last 1/4 to 1/2 turn or so
    16. Install magneto and get timing put back where it should be (line should be lined-up with center of hole) and use the Hand-Impact to set the screws. Be careful - these screws are itty-bitty.
    17. Make sure woodruff key is not a trapezoid. Replace if necessay. Install flywheel and torque to 120 to 140 ft/lbs.
    18. Before you install the electrical stuff take a few minutes to use a wire brush and clean all of the ground terminals. Hit all of the mounting areas on the block too. On 60hp bikes hit the steels that are inside the grommets in the black nylon housing.
    19. Check the wiring ground terminals too - replace any that look the wires may be corroded or crimped.
    20. For the rest of the male/female bullet connectors, use a green scotch-brite pad and rub off any corrosion. Then use some dialectic grease and get the electrical system installed.
    21. Look real closely at the main electrical plug. If you see any corroded or broken pins, it's time for a new harness. Both sides are still available.
    22. Now you can cleanup the mating surfaces of the motor plate and engine. Install new gasket and torque bolts down. New Lock Washers wouldn't hurt, but if you did a quickie, you're not interested in new washers are you?

    Break-In Procedures:     Mix up 5 gallons of 25:1 (double oil) and shake thoroughly. Now it's time to do a proper break in:

    1. Start bike and run if for 30 to 45 seconds (long enough to feel the heat in the engine.
    2. Shut it down and check everything over good. Let it cool down for an hour. Maybe put it on the trailer and head to the ridin' spot.
    3. With bike on the trailer, but backed-down far enough for pump to get enough water, start it and run it about 5 minutes if you can. Check for any water leaks, loose wires, weird things in the bilge, etc. Get it good and warm - but be sure it's not overheating. When you start to see wisps of smoke and/or smell the sweet smell of burning paint - you have a water restriction somewhere you need to fix. Shut it off.
    4. Let it cool down about 10 minutes before you hop on and take it for a ride.
    5. When it's ready, get on and fire it up. Take a good long idle around (about 3 to 5 minutes if you can stand it). Listen close for any anomolies.
    6. Now the hard part of the breaking begins. Slowly roll on the throttle until it "almost" comes up on plane. Hold it here for about 30 seconds or so (putting a good load on the motor and building lots of heat). Let it drop back to idle and putt around for about a minute or 2 to cool off. Repeat this cycle about 5 more times - and let it cool down good.
    7. This time, crack the throttle about 3/4 open until it comes up on plane - then roll the throttle back down to idle and let it cool off again. Do this for 5 or 6 times and then head back to dock/ramp area to let it cool off for about 20 minutes
    8. Repeat step 7 but come up on plane and ride around for about a minute or two. Increase the cooldown time to about 2 or 3 minutes. Repeat this for about 30 minutes or so, then back to the dock for a cooldown.
    9. Now, head back out with a long idle to make sure motor is warmed up good. Bring it up on plane and ride around - but never get over about 3/4 throttle (4500rpm max) for about 1/2 hour. Also, vary your speed too. Dropping down to idle and launching back up on plane is encouraged - with a twist. Hold throttle wide open, come up on plane and accelerate to about 4500 rpm then roll things back to just staying on plane - then slowly work back up in speed. By now you should be through about 1/2 of that 5 gallons of fuel.

    That First 50:1 Mix:       For the rest of the tank, repeat step 9 above. As you get down to that last gallon, you can start doing WFO blasts of up to 3 or 4 seconds.
    1. When you're almost out, you can put some regular 50:1 in there and repeat step 10. After you get that burned to about 2 gallons left, you can start increasing full-throttle-runs. Just be sure to let it cool down good. Look at the plugs occasionally. You shouldn't need jetting changes, but you never know.
    2. As you finish your 10 gallons, you can start opening her up for extended periods. Another set of plugs wouldn't hurt here.








    Copyright 2011 Capt'n Obveeus

  • How To - Engine Swap - 3 Cylinder Planning


    Engine Swap - Things to think about before starting a 3 cylinder swap


      More Speed - reality is same top speed

      More Power - a little more torque than 60hp wetbike

    • Mods - same as 60 but 1/3 more work

      Handling - will feel a little heavier than a 60 - especially in the corners

    Planning - What does the project entail?

      Engine Choices - differences through the years

    • Casting differences
      • Exhaust/bottom of motor is different (early years vs later years) 
      • Requires welding up of 1/2 of the exhaust outlet
      • Requires welding up of the motorplate to match water jacket routing and gasket sealing surfaces - see here
      • Oil Injection Systems - remove the pump shaft and make a block-off plate
    •  Ignition Systems - flywheel and stator assys are different
      • Early systems had symmetrical bolt pattern (4 bolts)
      • Later systems had one hole that was moved outward (flyer) and different flywheel
      • All electronic systems (no manual advance) had advanced stator setup and different flywheel
    • Pump Shaft Issue
      • Option 1 - rebuild 3 cylinder crankshaft and put 60hp lower wheel on (and run appropriate sized seals)
      • Option 2 - make a pumpshaft for a stock 3 cylinder motor
        • uses a stock propshaft, cut to length, and machine splines on one end
        • illustrated here
    • Throttle Issues
      • wetbikes use motorcycle-style pull-only hookup - outboards use a push/pull morse cable setup
      • ignition advance on early motors is controlled by a spring-controlled linkage - makes for a "GORILLA THROTTLE" - see here
    • Clearance Issues
      • Seat Height - interference with nylon seat bases?
      • Throttle - Idle position indicator
      • Coils - need to be relocated to right-side of motor (requires lengthening wires) - see here
    • Electronics Issues
      • Waterproof all connections required
      • Waterproof CDI and controller box on newer motors 
    • Throttle Hookup Issues
      • Mikuni SBN or BN's will require mechanical linkage between the carbs and a standard wheel on one of the carbs
      • stock outboard carbs can be used - AND - you can use a stock wetbike/seaflash style hookup
        • requires you to grind off the "mashed" end of the throttle shaft and drill/tap it for a tiny screw - see here and here
        • Then you use a stock throttle cable bracket on the top carburetor
        • Won't work on newer motors that have the throttle-position sensor on the middle carb (not enough room) - see here


  • How To - Fix A WPS Pipe


    How To - WPS Pipe Fix

    Parts Needed, Tools Needed, First Things First, Deep Inspection, Step 1, Step 2, Step 3, Step 4, New Bend Fitment, Mounting Pipe

    Topic:                           Fixing old rusted-out WPS Pipes

    Expertise Required:      Intermediate and above

    Estimated Time:            About 2 hours

    Parts Neeed:               You will need the following parts:

        • 180 degree bend from Summit Racingn

    Tools Needed:             You will need the following tools:

        • Bandsaw or hacksaw
        • Cutoff Wheel
        • 4 Inch Grinder or 90 degree pneumatic die grinder

    First Things First:           So, is your WPS pipe rusted out right through the bend at the bottom? It "might" be salvageable. That is, you need to check it over really good to see if it's worth fixing first.

    Be aware that there were several steel pipe designs and only 1 aluminum one that I know of. This tech article is limited to the steel pipes.

    Deep Inspection:           Ok - you need to get the pipe off the bike and on the workbench. The first thing you wanna do is give it a good visual. If you see rust-through on the water-jacked area, you can probably stop here. There's probably not enough left to start with.

    If things look ok - except for the 180 degree bend, then you are ready for step 1.

    Step 1:                             Get your air compressor setup with the blowgun that has the rubber tip. Set the air pressure to about 15 psi first.

    Old Style Pipes - Put the air gun onto one of the water intake nipples and put your finger over the other. If you can pressure it up without hearing any air escaping through the pipe (either end) - then that's spectacular. Jump to step 2.

    If you hear air escaping, then you probably have pinholes in the exhaust pipe under the water jacket. Game over really. If there's one or two holes, there'll be a hundred once it gets up to temperature.

    New Style Pipe - This is almost impossible to do properly since the water enters the exhaust pipe "inside" the water jacket. So, it's impossible to isolate one from the other - unless you cut the 180 degree bend off first. Here's a new style pipe.

    Step 2:                           Take a minute and find a plug and seal up one of the water nipples (if your pipe has 3, then seal up 2). Then increase the air pressure on your water hose and run it up to about 60 psi and check again. If no air is escaping, goto step 4.

    If you now hear air escaping you need to make a decision. You'll need to cut the water jacket off and fix any holes. That usually involves welding on patch panels - then welding the water jacket back on. Decide - is it really worth it?

    Step 3:                                Go to summit racing and order a new 180 deg. bend. Get the right one.

    Step 4:                               Take about 30 pictures of the pipe, the angle of the 180 deg. bend, the length of the ends on the bend, etc. Then take a sawzall or 4 inch cutoff wheel and lop off the 180 deg. bend about 1/2 below the weld where the water jacket is welded on.

    If you have an old style pipe, you'l need to be careful not to damage the two lower water nipples (water bypass hose).

    New Style Pipe - Now is the time to try to pressure-up the water jacket to see if it's leaking. You can either pressure up the exhaust pipe or the water jacket. The easiest way is to use an adjustable/expandable freeze plug with smaller washers. Shove that dude up into the pipe on the end you just cut off - and above the water holes. Tighten it down and pressure it up. You shouldn't hear air escaping through the water jacket.

    New Bend Fitment:                Take your time and lay the cutoff piece of pipe onto the new pipe bend. Leave about 1/8" of extra on the ends of the pipe so that you have a little bit of metal for final fitment. That is, you will probably need to file the pipe down a little to get the angle right.

    Also - if you have the old style, you'll need to transfer the water nipple to the new pipe too. It takes a bit of time, but you can do it.


    Weld the new bend in place and do a pressure test. This time, use a rubber stopper to seal up one end and a donut with the air hose in the middle on the other. Summit Racing has these too - or you might find them at your local radiator repair shop. Use a little soapy water to check for leaks.

    When you're done, it's time to mount the pipe back on bike.

    Mounting Pipe:              Take a few minutes and clean-out the groove in the bracket. Put a rag or something ahead of time so that you don't get anything sucked back into motor.

    Once clean, put a liberal dab of 5200 in the groove (about 1/2 way full) and mount pipe back in there.

    Now, unless you like the smell of burning Vinyl (on 60hp bikes) or burning fiberglass, you need to be sure you get your pipe installed correctly. Put the fastener through the upper mount (rubber mount) but don't tighten it down yet. Take a screwdriver or wooden wedge and put some pressure on the pipe to move it forward away from the hull and seat. Tighten down the upper mount now. Here's a pic of the upper mount:

    Put the springs back on - 2 is plenty.

    Put the intermediate exhaust hose, 180 degree hose, and lower pipe back in as well. Hint: Lean the last pipe back a bit before tightening down the hose clamps and it won't hit the head bolts (and leak).






    Copyright 2011 Capt'n Obveeus

  • How To - Front Ski (Alum.) - DIY


    How To - Build Your Own Aluminum Front Ski

    Parts Needed, Tools Needed, Step-By-Step, Final Plans, Weldment and Waterjet

    Topic:                           So, you wanna build your own aluminum front ski? Here's a set of drawings that you can take to get bids - or make a few changes and then weld up your own.

    Expertise Required:      Intermediate

    Estimated Time:            About 4 hours total

    Parts Neeed:               You will need the following parts:

        • Waterjet Machine Shop to cut the aluminum plate
        • Aluminum Welding Shop to weld up the pieces
        • Sheet Aluminum

    Tools Needed:             You will need the following tools:

        • Drill press to drill mounting holes
        • Countersink bit for those holes

    Step-By-Step:             Here's step-by-step instructions on how to get it done:

        • Take plans to a weld/fab shop and get them to fabricate it.
        • Can't find one that's reasonable, then have waterjet shop cut parts for you
        • Bend the main sheet yourself using a hydraulic press
        • Tig Weld the sides on

    Here's a pic of the one I used for reference. It's "before-and-after" set of pics.



    Right-Click and select "Save As" if you want to copy them locally and then print them.

    Plans                            Here is the final print - with notes and dimensions:


    Waterjet Cut and Bend  Here are the various pics that show the operations necessary to create the pieces for the weldment.




  • How To - Front Ski Bumper Install


    How To - Installing Front Ski Bumper

    Parts Needed, Tools Needed, Before You Begin, Dive In, Out With The Old, On With The New, Lining Things Up, What Should I expect? Care And Feeding

    Topic:                           How do you replace stock bumper with new elastomer type

    Expertise Required:      Beginner

    Estimated Time:            about only 30 minutes or so

    Parts Neeed:               You will need the following parts:

        • The new bumper kit

    Tools Needed:             You will need the following tools:

        • Allen Wrench
        • 2 x 4 about 10 inches long

    Before You Begin:         You will only need an allen wrench to install the bumper - but you might need a friend or cherry-picker (engine hoist) too to raise the front end up.

    If you get a 2 x 4 about 8 to 10 inches long, it makes a perfect "wedge" to put in between the steering tube and the lower foot to hold it up.

    Dive In:                          Get that baby up in the air and make sure it's stable. Wetbikes are top heavy, so be careful. Have that friend stand by just in case.

    Out With The Old:          Twist and pull on the stock bumper and it'll pull out. Some bikes might have a "cobbled on" bumper setup - usually with a long wood screw. Take all of that junk off and cleanup any sharp edges left behind.

    On With The New:           Take a minute to read the supplied instructions carefully.

    Follow the supplied instructions to get tab inserted. Hint: unscrew the screw almost all of the way out - only hanging by a thread. This makes it easier to get tab up and positioned correctly.

    Lining Things Up:         Get it lined up and tighten down the bolt. Here's a good example of bad alignment. Not quite centered.

    What Should I Expect?      Well . . . the ride is amazing. You'll probably wonder how you managed to live this long without one.

    Also, you can expect the bumper to loosen up a bit and move around. Just keep an eye on it and re-align and tighten it occasionally.

    Care And Feeding:              When sitting still or transporting, it's recommended to put some sort of block (or pipe) in the bumper. This wll keep it from sagging. There have been lots of different styles from wolmanized wood railing, pvc pipe (sinks unless you fill with foam), and wood blocks to nylon/plastic bar stock.





    Copyright 2011 Capt'n Obveeus

  • How To - Fuel Pickup Tube Replacement

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    How To - Replacing Fuel Pickup Tube

    Parts Needed, Tools Needed, Step-By-Step, Notes

    Topic:                           The Ins And Outs of Pickup Tube Replacement

    Expertise Required:      Beginner

    Estimated Time:            1 hour (not including time to clean out tank)

    Parts Neeed:               You will need the following parts:

        • Tygon Fuel Hose (1/8")
        • 10-0510-358 Fuel Strainer (only if yours is horrible)

    Tools Needed:             You will need the following tools:

        • Flatblade Screwdrive - for fuel filler neck
        • Battery Powered Drill - for phillips screws fill neck
        • Large Crescent Wrench (12" or larger) - for Nut on Tank Fitting
        • Smaller Crescent Wrench - to turn 90 degree fuel fitting
        • Berryman's B-12 Aerosol Carburetor Cleaner
        • Liquid Teflon Tape

    Step-By-Step:             Here's step-by-step instructions on how to get it done:

    NOTE: If pickup tube has rotted off - and filled tank with all of the old piece, it's time to bite the bullet and just remove the tank. That is detailed here: How To - New Wetbike Owner

    Disconnect Battery Before Doing Anything

    50hp Bikes:  

        • Remove the clamp on the fuel line and disconnect
        • Then unscrew the fitting from the tank and pull assembly out
        • Cut old tubing off and install new line and strainer
        • Put a dab of liquid teflon on the threads and reinstall. Resist the urge to overtighten - do not split the nylon and cause a fuel/vapor leak

    50hp Bikes:

        • Remove the clamp on the fuel line and disconnect
        • Grab both of your crescent wrenches and use them to tighten the nut onto the tank. You'd be surprised how tight you might need to get it, but don't go so tight that you tear out the material
        • With both wrenches still on there, HOLD THE NUT and unscrew the 90 degree fitting. You might have to try this a few times - but eventually it will break free
        • Once you get it unscrewed, carefully pull everything out of the tank
        • Remove the anti-siphon valve and spray it clear with B-12
        • Clean up all of the threads, install new tubing and strainer
        • Put a dab of liquid teflon on the threads and reinstall.


    There is some discussion and/or debate about the length of these pickup tubes. I prefer to make them long enough that they sit about 1/8 off of the bottom of the tank.

    There is also some discussion about whether the screen that's inside the strainer should be in there. If you remove it, be prepared to replace fuel filters regularly and/or clean out the anti-siphon valve on a regular basis.







    Copyright 2011 Capt'n Obveeus

  • How To - Ground Wires - Care & Feeding


    How To - Ground Wires

    Parts Needed, Tools Needed, How Can I tell? Where Do I Look?

    Topic:                           Care and Feeding of your Ground Wires. OMG - if there's one thing on a wetbike that will drive a person nuts, it's a bad ground connection. Here's a little blurb that will hopefully help you overcome any issues they create:

    Expertise Required:      Jedi

    Estimated Time:            About an hour

    Parts Neeed:               You will need the following parts:

        • Your brain
        • Possibly a new eyelet

    Tools Needed:             You will need the following tools:

        • 10mm Socket, 3 inch extension, ratchet and/or wrench
        • Maybe a soldering iron and solder if replacing an eyelet


    How can I tell?:             Many of us know that Wetbikes will attempt to make you look stupid when they can. Many times, you'll have a random issue that goes away only to reappear at the worst possible moment.

    Some of the symptoms of a bad ground are . . .

        • intermittent ignition cutout when hitting the water hard (landing after a jump)
        • funky miss in the ignition at low rpms that clear up when the revs come up
        • wires getting hot and/or discolored
        • ground wires getting brittle and/or beginning to corrode excessively
        • HUGE SHOCK when you hit the starter switch - sweet eh?
        • Discoloration of the electrical pins in the main wiring harness socket
        • Main fuse blows and/or looks discolored and like the solder has been melted out of it
        • Starter occasionally seems dead - or very slow to engage (but engages fully once it starts)

    Where do you look?        There are a couple of places to look for bad grounds - here are the most obvious ones:

        • Ground wire from battery should be connected to the bottom of the starter if possible. Clean/inspect as necessary. If running a Goki or S114-555, then connect this cable to one of the upper starter bolts.
        • If your starter switch (especially on pre-'85 bikes) gives you a jolt, you will need to inspect/replace the ground wire that goes from the base of the switch to the negative side of the battery. I think it's #21 in the parts manual.
        • Starter solenoid - there's a ground for the solenoid that goes to the mounting hole opposite the bellows. Clean it with a wire brush and/or make sure the copper strands aren't burned or broken. If they are burned - time for a solenoid.
        • 50HP motors - there is a ground wire connected to the Rectifier and one coming from the engine wire harness that are both grounded to the motor through the lower-left bolt holding the little mounting plate on the motor. Make sure the bolt - AND - the spacer are clean and making good contact. The CDI and COIL also have ground wires. Clean, inspect, and repair if necessary.
        • 60HP motors - On the left side, there are 2 ground wires. One is on the lower-left mounting bolt for the plastic assembly and the second is INSIDE THE WIRING HOLDER. The older style rectifier (bigger one that mounts on it's own special bracket) tends to corrode a little between "it" and the bracket. A little cleanup here goes a long way too. The newer, smaller rectifier is held onto the backside of the plastic holder with an O-Ring. It uses a separate wire for ground. Clean/Inspect/Repair as necessary. The coil and control unit (rev limiter) also have ground wires. Pay special attention to the coil ground wire. It's known to break the wire at the spade terminal - but look OK.




    Copyright 2012 Capt'n Obveeus

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