To caculate the neccessary changes if I change the sprocket size on my 05 gs? I want to change to a smaller sprocket. maybe a smaller rear sprocket (to increase top speed.) but not sure of the calculations needed to determine the new chain size. any help is apreciated.

You will not increase top speed simply by putting on a smaller rear sprocket - the motor does not have the power to pull redline in 6th gear in stock form.  You will increase the theoreticl top speed - but the on-the road top speed would likely go down.

Team Evil Pumpkin racing at http://www.evilpumpkinracing.com/ used to have an excel spreadsheet for seed in gears for the GS500 - give them a try if you want to see the theoreticl effect of different gearing and tire sizes on the GS

It would be both cheaper and easier to go up to a 17-tooth sprocket in the front.  (One tooth up in the front is worth almost 3 teeth down in the rear.) 

You can usually get away with going up/down one tooth without having to change your chain. 

On top of all that, you would decrease the wear on the front sprocket without increasing the wear on the rear sprocket.

See the Chains & Sprockets page for a couple of sources.

yea but i would be nice to cruise at 5k or less at 70-80 than the 6-7 k that i am at. would save wear on the engine, even if top end would suck.

i would do the rear. that way you can get a dif sprocket set and change it easly if you deside to do a mountain or trackday ect...


i may look into this for my touring setup. would be nice

I would go with the 17t front sprocket, or a larger rear tire, both have the same effect.