Can a pedal sprocket be used on the motor side?

Discussion in 'Motorized Bicycle General Discussion' started by silverbear, Oct 16, 2010.

  1. silverbear

    silverbear The Boy Who Never Grew Up

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    I have a budget build coming up on a 51 Schwinn bike with a HF motor. I'm planning to use an EZM tranny for it (which will come later when I can afford it) and am doing everything else on as low a budget as I can all the while trying to do the build well. I'm all tapped out financially right now, but want to get the bike ready for the motor and transmission. Much as I love the MM hub adapter and sprocket, I'll be doing the rag joint on this one and want to do it as well and as carefully as I can. I know it can be done well as it has by others. With the setup and gearing I have in mind I would like to use a 64 tooth sprocket on the motor side as the driven sprocket. It is a very nice one which came from a high end Schwinn exercise bike maybe thirty or forty years old... chrome and heavy metal. So here's the question... will the teeth of that sprocket encounter any problem running #41 chain? Are they compatible? If not, then back to the drawing board. If it is then I have to figure out how to drill holes to match the 2 stroke kit rag joint sprocket... assuming that sprocket is concentric to begin with. I can save a good bit of money using what I have on hand if this will work. Any suggestions on drilling out the new holes accurately? I don't have a drill press. Thanks as always for the good advice I find here.
    SB
     
  2. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Lay a kit sprocket on top of it & trace the holes! ;)
     
  3. silverbear

    silverbear The Boy Who Never Grew Up

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    Venice,
    I figured that and was also thinking about clamping the two together with C clamps to act as a kind of template and drill guide. I would still use a punch and drill a pilot hole.
    So, will a pedal sprocket work with #41 chain?
    SB
     
  4. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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  5. WildAlaskan

    WildAlaskan New Member

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  6. bairdco

    bairdco a guy who makes cool bikes

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    as long as the holes are straight, it'll work. take your time, get out your compass, whatever it takes...
     
  7. tommyboy1442

    tommyboy1442 Member

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    anything is possible with a goal and the will, and yes the money as well. take your time and keep it kustom...rushing it or not having the whole picture in mind as of what you want to do before doing will result in poor quality.... for my setup here i wanted a nice looking sprocket as a pose to a solid piece of chinese metal-lol so i went and bought a nice cncd billet flame sprocket, same as on pedal side so i could having matching kustom sprockets.i took a flipflop hub with sealed bearings for $20.had the hole lathed out to fit snugg over the hub, then welded an adapter to the sprocket, taped the adapter with set screws to hold the sprocket from spinning.also i had it machined to where you have to heat the sprocket to fit over the hub for a nice tight fit. came out awesome now just needs polishing....
     

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  8. curtisfox

    curtisfox Well-Known Member

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    They used to sell a drill bit (maybe ACE ) that has a small pielet point. So you can put it in the hole and it will drill the center first then fallow with the rest.(center point drill?). And you could maybe tape a level bubble on your drill?
    As far as the 41 chain its the same pitch as the bike chain just a little wider.
     
  9. silverbear

    silverbear The Boy Who Never Grew Up

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    Thanks for all the good advice, you guys. I'll return to this thread with the results when I have some. Tommy boy, that sprocket looks great!
    SB
     
  10. msrfan

    msrfan Well-Known Member

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    Hey, SB. I have a couple of those huge sprockets and I adapted one to a moped hub and used it on my 8hp Briggs bike with 41 chain. It worked great but I still needed more teeth, so I took it off. Mounted with a rag joint should give a little room for adjustment if your new holes are a tad off. So I have an extra if you mess it up.





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  11. RedB66

    RedB66 New Member

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    I've used several regular sprockets. The hole for the crank pin lines up perfectly with the nine hole pattern.
     

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