I am now using a 42 tooth sprocket but i purchased a new 44 tooth rear sprocket for my raptor and my chain is just a bit short to use without adding another master link so i am going to use my 20" tires instead of my 22"which i usually run.My question is wouldnt that be about the same as going up two teeth in the rear?I know this could probably be researched and i could find a chart somewhere but i am feeling lazy tonight so i figured that someone else has calculated this out and will share some information.

 

To be absolutely sure, measure the two tire diameters or circumferences to see what the true measurements are. You will be surprised by how much tires vary from what they are claimed to be.

If they are 22 and 20 inches, that is about a 10% change. A 10% change on the sprocket side is about 4 teeth in the rear or about 1 tooth in the front.

So if you want to run the 22's, and use your 42 in the rear, but want more accelleration and low end just drop a tooth in the front. You should have enough chain adjustment to accomodate this. Good luck.

RR1

 

If you have microsoft excel you can paste this formula in cell "D2" =(A2/B2)*3.14*C2

Where
Cell A2=counter sprocket
Cell B2=rear sprocket
Cell C2=tire diameter
Cell D2 calculates inches of ground covered by the tire at one revolution of the counter sprocket

You can then change the sprocket sizes and tire size to compare.

To directly answer your question, a 13 - 44 with 22" tires is equal to 13 - 40 with 20" tires, they both cover 20.41" per revolution of the counter sprocket.

 

Ahamay17-Thanks for the information but HUH?

 

I think it will be a like going up a little more than 2 teeth in the rear. I think it is more like a 4 tooth diference. Just an offhand guess though.

 

If you drop the rear tire size to a 20" you will need to drop the rear sprocket to 40 tooth to keep the same gear ratio that you had with the 22" tire and 44 tooth sprocket.

 

here you go

gear calculator

 

BURKEDADDY-Thanks for the gearing caculator site it looks very useful and that is just what i was looking for.