Gearing for 18" tires on R?

[DixiePlowboy]

I'm thinking of switching from 20" tires with stock gearing to 18" tires. I want to retain at least as high of an effective gear ratio as I have now as I don't want to lose any top speed. Will a 14 tooth front suffice, or will the rear sprocket need changing, too?

[JohnR.]

Look at it this way, you are going down 2 inches which is 10%. You'll need to either go up 10% in the front (1.3 teeth) or down 10% in the rear (3.9 teeth). Basically either go to a 14 front or 35 rear. I'd say go to a 35 rear unless you have an aftermarket case saver that'll let you run a 14 in the front.

John

[DixiePlowboy]

Do you know of a source for a 35 tooth rear sprocket for an '85 model? All I can find are no less than 38.

[DOGBONE]

Sidewinder Sprockets will make you a custom sprocket. I've called them to see if they would and they said yes. Just dont know the cost.

[DixiePlowboy]

Thanks yall.

[JohnR.]

You can get a 36 for the rear. I am sure James Lucky has them.

John

[PLJ.]

My favorite gearing with 18" Holeshots is a 14 tooth front with a 37 tooth rear. Lots of top end with not much loss in the basement.