pinion and spur
 

i have gone brushless in my bj4 we and was wondering whats the best pinion and spur combination for a x11 7.5 with a nosram speedo

mike :)

7.5 is the 2 star equiv right? if so then a 16/17 should work fine on the standard 78 spur.

I run a 5.5 on 15/81 - for a 7.5 you could proberbly go 2 teeth higher.

if you want to keep the 78 spur then go for 16/78 as a start.