Yeah, I need to play with it a bit tonight, I want to runn smaller spurs to help move the motor down, etc. So if I run the same ratio that works on a 68 or 65 tooth spur on a 54T spur I should end up around where I want to be. Compared to the first set you sent me, a 19t pinion and 54t spur should yield the same numbers. I'll have to play with it more. I was kind of looking for the "easy answer" with someone who ran an ERBE in racing consistently, but I'm starting to think most are using 5s or 6s and lower kV ratings.