Originally Posted by Fred Hubbard

You should be able to use the same spurs being used on the TCX, the hole pattern for attaching the spur hasn't changed. The motor mount now has 2 vertical holes as well so if you do use a small spur you don't have to try and go through the hole nearest the center pulley to try and attach the motor.

Originally Posted by wwddww34

The spur has to have a 4-hole pattern just like the Xray spur gears have. There are a handful of spur gear manufacturers (e.g. Xray, RW Racing, Kimbrough) that put this hole pattern in their spur gears.