Before $100+ 3 pc cranks were here were their good 1pc offset available

Discussion in 'Motorized Bicycle General Discussion' started by buck1234, May 1, 2013.

  1. buck1234

    buck1234 New Member

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    Hi All;

    Just shopping earlier and since I won't race or use the pedals much, that's what the engine is for. Can you fellows suggest a good quality offset crank assembly for my Huffy Panama Jack build?
    Good shape used is just fine.

    Thank you

    Buck aka buck1234
     
  2. bairdco

    bairdco a guy who makes cool bikes

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    older Wald one piece cranks are made in the USA and you don't have to bend them to clear a china motor.
     
  3. chainmaker

    chainmaker New Member

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    A set of whizzer cranks will work as well.
     
  4. bigbutterbean

    bigbutterbean New Member

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    I dont think a whizzer crank will work. I'm good friends with jbcruisin,and he has quite a few original whizzers. The whizzer engine crankcase was designed to fit between a bicycle's stock pedals, and I've seen his collection, none of his bikes have offset pedal cranks. And although a 4 stroke is also a china motor, its wider than a 2 stroke and stock pedals may not clear it. Buck, I recently built a 98cc cruiser (described in my signature), and I actually had an offset one piece crank that was still not wide enough. I went to Lowe's ( Home Depot carries them as well) and bought a propylene ( NOT propane, propylene, comes in a yellow cylinder) torch with the nozzle included for $50. I put my crank in a vise (with some help from a friend) and we heated the arms till they got red-hot, then put a seatpost (any pipe will work, but a spare seatpost was handy) over the arms and bent them, out in one spot on the arm, back in at another, so they would still line up straight. Once you get them red-hot, they bend like butter. Let them cool at room temperature so they don't lose their temper or become brittle, and you're golden.
     
  5. bairdco

    bairdco a guy who makes cool bikes

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    buck, if you're building a 2 stroke china, you can use the same bending technique with the stock one piece cranks that come on your bike to clear the motor.

    if you're building some monster engine, give us some more details. i'm sure someone here has already done it.

    oh, and if you are building some monster engine, you might want to re-think putting it in a Huffy... :)
     
  6. buck1234

    buck1234 New Member

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    Bairdco

    No monsters in my future. Just a 142f. I've heated and bent my share of steel and try to stay away from the process. Peening the heated area when cooled and re heating to realign the steel was standard practice where I worked. Still a chance that it just got too brittle. Would really hate to be on a standing down stroke and have it snap and leg goes down and false hip shatters the bones.

    Buck aka buck1234
     
  7. chainmaker

    chainmaker New Member

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    Don't know about the HS but, I have used the whizzer cranks on a china and a HF79, I guess with the 4 stroke it really depends how high you mount the engine and how much clearance you need.
     
  8. bairdco

    bairdco a guy who makes cool bikes

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    older, US made cranks are cold forged. if all you need is a little clearance, you don't even have to heat them to bend them. just take them off (never try it on the bike. cranks are stronger than mild steel bike frames) wedge them somewhere, put a pipe over them and yank on it.

    speaking of broken crank injuries (not those kind, get yer mind outta the gutter :) ) years ago in my bmx days my buddy landed a huge stair drop, his leading crank arm broke, the bike freewheeled and 4" of broken crank penetrated his calf.

    pretty disgusting. his foot was on the ground (which probably stopped the crank from ripping his leg in half) and his bike was stuck to him, using him as a human kickstand.

    lucky thing was, we were in the hospital parking lot. we got to watch as the paramedic seperated him from his bike.

    he healed up fine, eventually.

    i remember this now, because i need to make some wider cranks for my bike, and i was thinking about what could go wrong...
     
  9. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

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    Whizzer motors do not fit between stock one piece cranks.
    Yes, the Whizzer cranks aren't offset but they are wide.

    They use wide cranks that can be used for most of the 4 stroke builds.

    [​IMG]
     
    #9 MotorBicycleRacing, May 3, 2013
    Last edited: May 3, 2013

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