I don't know. I understand Mike's post about the wear factor, but look at the inout gear of a Revo transmission; it has far fewer teeth than the first or secong gear and it wears just fine. The last time I took my Revo tranny apart, that small gear still looked pristine without a hint of wear. I really think a perfect gear mesh matters a lot. Of course, by the time the power reaches the transmission, it has already been reduced in rpms by the spur/pinion...

Again, it's 12 or 14 against 51.. the wear is an obvious result.

So for every 4 hardened pinions you wear out, you need to replace the hardened spur?

13t and 14t gears for sale.

Artur