"GearingCommander"

[DarthRider]

This is a pretty cool site for gearing information. Ratios and all that and more ! Like what effect any given gear change will have on required chain length.
And not just calculated ratios & effects...it's based on actual gearing specific to a database of 234 bikes. It factors in wheel/tire sizes and available max RPM.
Interesting & useful !

http://www.gearingcommander.com/

[DarthRider]

Thought I'd bump this older thread on gearing.
What with BMWs having chain drive now and people on the Cafe' actually building & racing motorcycles, it might be useful.
It now has over 500 bikes in the database and is customizable as well.