Originally Posted by
freebird
It all depends on your Track size that you run on for the FDR. Most of the folks who went to smaller spur gears do so for the reason of moving the motor away from the rear wing. With the larger 96 gear when you roll over or have a wreck the rear wing will most likely contact the spur and bur the spur which will then affect gear mesh and you'll end up stripping the spur in short order. Ive gone down to a 90 and 92 and also made a little notch in the rear wing where it would clear the spur if and when contact could happen.
That's called a spun spur.