# Coopting Bicycle Gears?



## austenandrews (Aug 22, 2010)

I'm pondering the idea of using a bicycle chain and gears to get the right rpm for a build. Does anyone have experience with this? Any land mines to look for?


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## Diabolik (Apr 19, 2007)

What sort of motor/RPM are you starting with and where are you trying to end up? I used a chain gear reduction to take a 12 RPM gear motor down to 6 RPM to drive my rowing skeleton and it had monster torque. If you are using a wiper motor and really need to slow it down you may consider just using a PWM speed controller instead.


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## austenandrews (Aug 22, 2010)

Taking a motor from 30 rpm to 60 rpm, to continuously drive a 3' diameter 3D zoetrope. It'll need torque and my current motor has enough. I just don't know if adapting a bike system would make it easier or harder.


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## Diabolik (Apr 19, 2007)

That should be an easy enough ratio to achieve. You may want to check out surplus center.com . They have a ton of sprockets, bearings, and chain related stuff. You might find it easier to get everything you need to match up such as shaft sizes and chain size.

The only other tip I have is to make sure you build your motor mount with a slotted base so you can get the proper tension on your chain.


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## corey872 (Jan 10, 2010)

Could certainly be done, though it does introduce more complexity, another point of maintenance (lube, tighten chain), possibly more noise (if that is an issue). A cogged belt drive might also be an option to reduce some maintenance and noise.

I would also note, some motors / shafts, etc aren't really meant for a 'side' load...ie the way the chain tugs the shaft to one side. This is especially true of motors which have bushings vs bearings. Likely not the end of the world, but something to consider if you intend to use the motor for long periods / heavy use.

You might also consider the cost of chain, sprockets, axles, bearings, tensioning mechanism, etc - vs just getting a different surplus motor at or near the desired RPM.


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## austenandrews (Aug 22, 2010)

I was hoping to use the components straight from the bike, but I think the freewheel kills the deal anyway. I don't want an extra brake mechanism.

Many thanks for the help.


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## BillyVanpire (Apr 22, 2015)

i think you might have an easier time using wood gears...no really, watch izzy's video






edit: izzy makes a rotating display which might be helpful


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