20 toothe sprocket?

Discussion in 'Motorized Cruiser Bicycles' started by \./, Dec 4, 2011.

  1. \./

    \./ Member

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    so i have a late 70's schwinn cruiser that i have been working on, however, i cannot get my 36tooth sprocket to bolt on right (i guess its crooked because my chain falls off) can i flip my wheel up side down and use the 20 tooth thats meant for pedaling? (the bike had coaster brakes so the freewheel doesnt spin either way)
     
  2. diceman2004

    diceman2004 New Member

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    no you can,t flip it over .... and yes it does freewheel one way . but it only works properly if the brake arm is attached to the frame . The wheel will spin forward without turning your pedals .

    if you try to see if it freewheels in the air ... off the bike .. by turning the sprocket , and its not freewheeling , it because turning the sprocket backwards engages the brake .

    keep trying to get the 36 on , even if flipping the wheel would work ( which it won't )
    20 teeth is way too small for the motor .
     
  3. \./

    \./ Member

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    i took the pedals off so im not concerned about it. ive been trying to readjust the 36t for quiete a while and nothing seems to work. also, i cannot get the engine started. seems like ive encountered a problem with every step i took.
     
  4. 2door

    2door Moderator
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    What's your spoke count? 32 or 36? It makes a difference.

    Suggestion: Put the pedals back. Without them you have a motorcycle, not a motorized bicycle and you'll fall under the same rules as a motorcycle, in any state.

    Tom
     
  5. \./

    \./ Member

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    36 spokes

    i looked into CA laws and from what ive seen, a bike without pedals is considered a moped and doesnt require insurance / registration as long as top speed does not exceed 25mph.
     
  6. 2door

    2door Moderator
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    36 spoke count should not cause you any sprocket install problems. What in particular are you have problems with?
    Tom
     
  7. \./

    \./ Member

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    the sprocket doesnt seem to allign with the motor without clearance issues. the chain rides up the sprocket after a few feet (travel) then falls off
     
  8. 2door

    2door Moderator
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    Chain/sprocket alignment is critical. So is the tension.
    You'll have to concentrate on getting the rear sprocket aligned perfectly with the engine drive sprocket. Very little lateral misalignment is allowed. Some kit supplied sprockets are flat where others are 'dished'. That means the teeth are offset to one side. If your sprocket is flat you'll have to determine which way it needs to go, right or left, to get the chain path straight. Sometimes that means shimming the rear wheel off to one side or the other and/or the sprocket. If your sprocket is the dished type you can flip it to move the chain in or out.
    There are other methods but keep in mind that clearance with other parts, such as the bike frame and rear tire, is also important.
    The rear sprocket also MUST be centered on the hub and have no wobbles either vertically or horizontally. It must spin true.
    Are you using a chain tensioner? If not, the alignment is even more critical. If you have a tensioner it can help with slight side to side misalignment because it can assist in 'guiding' the chain onto the rear sprocket, if installed correctly.
    Keep us informed and ask if you need more help.
    Tom
     
    #8 2door, Dec 4, 2011
    Last edited: Dec 4, 2011
  9. \./

    \./ Member

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    thank you for all your help
    im just not having any luck with this wheel. i found some1 (with experience) whose willing to help me finish it up for a decent price. i might just take him up on that
     
  10. \./

    \./ Member

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    so far...

    [​IMG]
     
  11. \./

    \./ Member

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    update:

    turns out my chain was riding up the sprocket becase the teeth on the sprocket were flat. some1 suggested that i file them to make em sharp and it worked. i got the bike started but the engine dies very quickly (doesnt idle), and i cant accelerate even though i twist the throtle. should i mess with the carburator some more?
     

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