78T or 82T spur gear
 

since I've got my xx4 in bits at the minute after stripping another spur gear, I can replace it with either 78T or 82T. Some (alot) of the setups ive seen show 82T + as the norm. Why? what difference does it make?, faster top end?

Thanks

depends on what motors your running, and how small a pinion you need to run

If you run a 78 spur the smallest pinion with the lowered motor plate you will be able to fit is a 19tooth.

also unless your using the kevlar spur gears,
the purple one is 84 tooth
yellow 82
lime green 88 but without modification wont fit
white 78
black 76
red 86 again doesnt just fit in without mod
we tend to use the 84 purple one most of the time , but thats so we can run 15-16 tooth pinions for brushless
hhope that helps

hmm, typical me, I never even considered what would physically fit doh...now i need a chart or something because removing all those screws again without being forearmed is just too much hassle :)

Neither I'm running an 86 spur on my XX4. You will need to to do chassis mods to get it to fit properly.