where do i find one? (need a small light v-drive for 40-50 hp 2 stroke)

Discussion in 'Inboards' started by racing fan, Feb 14, 2011.

  1. racing fan
    Joined: Nov 2010
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    racing fan Senior Member

    i need a small v-drive like 10lbs (light) fora 40-50 hp 2 stroke up to 8000rpm
     
  2. CDK
    Joined: Aug 2007
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    CDK retired engineer

    You probably won't, even when you allow for twice the weight.

    A 2 inch timing belt drive is feasible though. With alloy gears, hollow shafts, sandwiched between aluminum plates and all unnecessary material removed by punching holes, the weight could be 10-15 lbs.
    All you need is a good machine shop to build it for you.
     
  3. Boston

    Boston Previous Member

    go to a surplus store and buy a few pulley's, use a few belts if you have to although the chain drive is a more efficient rig (CDK's suggestion) so maybe a junk yard. Deal is that your going to need a drive shaft that fits and machine work isn't cheep. Thus the suggest of the pulley's. Most of them will have a simple keyed center and your likely to find something cheap that will be able to handle that little torque.

    my two cents
    B

    PS
    go to a motorcycle salvage and use a drive chain. take the rear sprocket and the transmission while your at it and after that you only need to attach one of the sprockets to the drive shaft ( might be harder than you think, depends on the drive shaft I suppose ).
     
  4. claydog
    Joined: Dec 2010
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    Location: michigan

    claydog Junior Member

    Sounds like a snowmobile CVT set up.;)



    OP
    In fact it 40-50 hp 2s that turns 8000rpm sounds an awful lot like a 550+\-CC air cooled snowmobile motor. Transmision weight is gonna be in the 20# range for both clutchs and the chain case (chain case maybe not needed in your case) but does give you a very tuneable transmision. If this is the route your thinking of taking most newer 2S snowmobiles get a "reverse" gear by reversing engine rotation.
     
  5. racing fan
    Joined: Nov 2010
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    Location: U.S.A.

    racing fan Senior Member

    i am not making a trans i am trying to use this motor in a small hydroplane and i cant put it in the front so i need it in the back so i need a v-drive to get the angles right not i messed around with the motor bored it and changed the stroke and added vec. stacks so it runs higher rpm and more torque and i talked to some boaters i know and they use to have v-drives rated to 50hp so what can i do i just want to go from straight shaft to bit i would like neut. but i will do just forward but i want to use chains no belts i hate belts
     
  6. stupidbaker57
    Joined: Jan 2011
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    Location: Lakeville Ma

    stupidbaker57 Junior Member

    I've drawn out a "V drive" set up for my 8 foot Glen L Pee Wee boat. The prop shaft is around the 3 foot length. The chain box is fabed up to house 2 chain sprockets and a chain. The box is bolted onto the engine (I'm using a horizontal lawn tractor engine). The engine/box combo mounts in the rear of the boat at a 12 degree angle so there won't be any u joint issues. The prop shaft runs in a tube, thru the bottom and bolts up to the strut on the bottom of the hull. A transom mounted rudder will be used due the the lack of any more boat aft of the engine. This will be built out of steel. If it works out as expected, then I'll make anthoer one from aluminum.
     
  7. stupidbaker57
    Joined: Jan 2011
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    Location: Lakeville Ma

    stupidbaker57 Junior Member

    The small runabout project has been put on hold (at the monment) to work on a 3 point hydro. Will a surface drive like this work for your project? No V box is needed. This one has a trimmable shaft angle. Dave DSCF0008.JPG

    DSCF0009.JPG
     
  8. Easy Rider
    Joined: Oct 2009
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    Easy Rider Senior Member

    Look at ultralight aircraft hardware.

    Easy Rider
     
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  9. stupidbaker57
    Joined: Jan 2011
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    Location: Lakeville Ma

    stupidbaker57 Junior Member

    How about a "dropdown box" for a snowmobile.
     
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