gears gears

[jacksit]

running a 15 62 set up 34 1/2 " r rear on a cloen purple plate eng. 5500 rpms want to turn about 6000 at hunterstown some say go down 2 or 3 teeth and some say to go up. witch way ?

 

[bpoirier]

You could drop one tooth off the driver or take the rear gear up to a 65. That should get you in the ballpark.

 

[Bluegrass855]

More teeth on the back higher RPM, less teeth on the front higher RPM. I would try a 15-65 to 15-66

 

[MikeleoneCT]

More teeth on the back higher RPM, less teeth on the front higher RPM. I would try a 15-65 to 15-66

Agree, General rule is 200 rpm increase for each tooth added to the rear sprocket. I assume the clone has a big pipe on it. Otherwise 6000 would be too much

 

[alvin l nunley]

Agree, General rule is 200 rpm increase for each tooth added to the rear sprocket. I assume the clone has a big pipe on it. Otherwise 6000 would be too much

I have this collection of spreadsheets, and it's in situations like this when they come in handy.

Let's assume a 16 – 65 gear ratio with 34 inch tires and 6000 RPM. MPH = 47.58
let's change to a 16 – 66 one tooth more ------------------6103 RPM. MPH = 47.58
there is no general rule. The amount the RPM will need to change, with a change of one tooth on the axle, changes with the gear ratio being used. The lower the gear ratio, the more rpm you have to turn to maintain the same top speed with a one tooth change on the axle.

From the desk of Al Nunley
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory. (Al Nunley)