Using hardened steel R.R. spur on 5mm 32 pitch pinions

[BrianG]

Yeah, the shape of the teeth from a normal steel pinion and a hardened steel spur are different and bind quite a bit. You can even tell that by trying to spin the pinion on the spur by hard. The binding was probably what made it go slower and is definitely where the filings came from!

I'm not really sure what tooth pinion you'd need. I would use this page to figure out what pinion you need. First, enter all the values from a stock emaxx except leave the top speed blank. Write down the top speed and overall gear ratio. Then, clear the form and enter the total gear ratio and top speed calculated from before and the rest of the values, but leave the pinion blank this time. The calculator will figure out the pinion to use to get the same overall gear ratio and top speed.