Originally Posted by 8ight-e

Actually it if anything the 43t would limit gearing options.. as you would be limited to 18 or 19t max, either spur will accept down to a 11t on a typical 4.5 motor with stock rotor. Gearing changes obviously for different kv's.. but you get the idea of the relationship and why it's pointless to waste the effort imo. But to each his own.. if you're bored I guess it's something to do :P

14t pinion on the 43t (~41)
13t pinion on the 40t (~41)
13t pinion on the 43t (~38)
12t pinion on the 40t (~38)
12t pinoin on the 43t (~35)
11t pinion on the 40t (~35)