Chain Saw Bike Gearing

jjjd · Mon Mar 12, 2007 8:44 pm

Hey guys, i am going to be mounting a chainsaw on the back of a pedal bike and making it chain driven(just seems easyr than friction drive) And i was wondering what sized gears i should use, i already know to have a small to big, bit aroung what size teeth? I may not use a chainsaw though, im looking at either that or snowblower engine.

Thanks, Andrew

WOW!! · Mon Mar 12, 2007 9:25 pm

I would go with a 10 on the saw and a 60 on the bike. That will give you tourque and speed. Or you could get a mountain bike and mount it in the frame like a motorcycle, this way you can shift.

jjjd · Mon Mar 12, 2007 9:29 pm

iv tried to make one that can shift but it never worked out, everytime we went to shift the chain just fell off, but thanks for the gearing

Andrew

pyrogeek · Mon Mar 12, 2007 10:45 pm

I've seen a lot of bikes and scooters using chainsaw engines, and most use pretty big drive sprockets. Like, about the size of the rim of the tire.
The problem with giving specific numbers for something like this is that you failed to mention what size wheel the engine will be driving since the wheel factors into the gear ratio.
If you have a 20:1 gear ratio on a 12inch rim, it will be much different than if you put that same gear combination on a 24inch mountain bike rim. Also, how much do you weigh and what size engine? If you are only like 120lb and the chainsaw is like 45cc, it will be different than if you are 350lb and the motor is like 30cc.

A snowblower engine would be great. If you could find like a 5hp 2 stroke, that would kick butt. I saw 2 stroke since they can be ran sideways and not risk any damage being done, and they are lighter than 4 strokes.

Here are a couple links for your researching pleasure.
http://www.tziscooterworld.tk/
http://www.greenspun.com/bboard/q-and-a ... _id=004zEW