zenish, my old ring and pinion gears were 4:11 (37 teeth on ring and 9 on pinion) that calculates to 4:11. The new gears are 3:55, at least thats what I ordered as advertised as 3:55.
It may be the tires that make a difference. Once I am able to check the mph, and tire heighth, I can calculate my rpm's. Only other thing maybe is what Red58 said, maybe I am being fooled by the sound and feel. This is a fresh rebuild and sometimes to much caution on a test run may have done me in.
