Sprocket Sizes

[3nracing97]

I have heard a couple different opinions on this and am not sure what is true. Would you want a smaller front sprocket or a larger? My thinking is I would get more torque with the smaller sprocket but I have heard from a few people that I need to run the 16 tooth sprocket. I am new to 600's so any information is good information!

Thanks

[Bill]

Finding the correct gear ratio for your car, with each track you run on, is very important. Most people use a tachometer with a memory, so that they can see the maximum RPM the motor ran at during a race. Ideally you would like the tach to show an RPM reading at, or just below the rev limiter. To get more RPM, you will need to either add teeth to your rear sprocket, or remove teeth from your front sprocket. As a rule of thumb, each tooth you add to the rear sprocket will give you about 300 RPM. Every tooth you remove from the front sprocket will add about 1,000 RPM. And, of course, reversing the process makes the RPM go down.

Hope this helps.

Bill

[racer58]

I run a 14 tooth on the front and use the rear sprocket to make changes. Your best bet is to find someone at the track you run with a similar motor set up to get a good starting point. You can use your tach like Bill said or can start going with bigger rear sprockets until you start hitting the limiter then adjust down from that. Good Luck!

[3nracing97]

Thanks for the help. I know with go karts and bandoleros we could actually gain some speed by running different sprockets but still having the same ratio. If I am remembering correctly by running a smaller front sprocket we could get more torque than running the same ratio but with a bigger front sprocket. I know it really shouldn't matter because you are still running the same ratio but it did work and I was wondering if it works with the 600's.

[DaddyZ]

per Steve Smith's book running a smaller front/larger rear sprocket to achieve a particular gear ratio will lower the front of the chain, which acts like a torque arm under acceleration, forcing the left rear down into the dirt. As far as an increase in actual torque I can't say I've ever heard that.

[bcbart82]

I understand what you are saying about the front sprocket increasing torque. No matter what sprocket sizes you used to obtain your ending gear ratio it seems a smaller front sprocket would be easier to spin and get going. Now whether that truly increases torque I could not say but it makes sense.

Bart

[racen12]

A smaller front sprocket can cause binding and cause hp loss
but the sprockets should work just as your others did
the chain does act like a torque arm

[jakefife]

Has anyone messed with gear ratio vs roll out per gear ratio. Road race bicycles use this alot.