cim motor power question

[Kit Gerhart]

Originally Posted by Zippiot

i was just suggesting using the 6 inch tire and the 3:1 ratio because a smaller tires is much easier to move. we do have 10 inch tires that i wud much rather use, and if i found a 50 tooth sprocket i thin i can make it work.
10 inch tire and 5:1 ratio will yeild 25 mph at 4320 rpm, thats seems like a decnt top speed to me. and with the light weight frame the motors should be able to move off the line, this is looking good so far guys. now all i need is a 50 sprocket gear...does anybody think a 40 tooth would work with the 10 inch tire?
10 inch tire 4:1 ratio will yeild 31 mph at 4320- rpm...that seems a little fast can the motor get us off the line?
(i have a 40 tooth already so if this will work i would muchn rather use it)

The 31 mph @ 4320 rpm is probably "higher" than is likely to work very well. If you have a way to attach them, you can get bicycle sprockets from 9 or 10 to more than 50 tooth. Bicycle chain isn't as strong as what you might be planning on using, but it should be strong enough.

How do you plan to control the motors? Are you using some kind of electronic speed controls? If you just "throw a switch" to start your machine, you are going to be pulling very high current longer than you will want to, but if you can work your way up to speed at part "throttle" with a speed control, things will be much better.