Sprockets sprocket to connect 49cc to 21 speed



Is there a sprocket for a pocketbike engine that will allow you to connect the engine to my mountain bikes gear system?

The chain on a mountain bike is much bigger than the chain on the pocketbike. basically I want to be able to use the bicycle chain and connect it to my pocketbike engine.

Is there anything out there that will do this?


i'm sure what you have in mind is doable...someone is bound to have some ideas...perhaps if you post a little about yourself in "introduce yourself" you'll make some new friends who are working on similar projects.


You'll probably need a jack shaft to transfer the power to the right hand side. Search for jack shafts. Also, there are some guys like Zombie Builder who do incredible work. It's well worth the time to see some of the things that have been done.

Earth Mechanic


Ive been doing some checking on this and alaskavan is right, you will need a jack shaft. Beyond zombies amazing bikes, the trouble with a regular bike is that they only have one bottom bracket and you need 2 bottom brackets to run a jack shaft. So, unless you design a special system you will need a bike with two BB's that are spaced at least 8" apart from center to center. You might check out the Giant stilletto, there are two BB's and there is a company that makes a special gear box and mount for this bike (cant remember who right now). The best would be to take a regular cruiser frame (a sturdy one) and cut it, and elongate it and add a second BB on the chain stay 8 inches or so behind the front bb. that would give you space for the jack, and you could mount the motor between the seat tube and down tubelike a regular four stroke> you could also weld on a second bb in front of the wishbone on a stretched cruiser which is basically what zombie did> probably easier than cutting and all that>