Senton weird grinding noise

[BIGBOI]

I ran my senton 4x4 mega today out on the wet tarmac of my driveway and after about 5 minutes I heard a grinding noise. Once i got up to a higher5 speed the grinding stopped, but it came back. hardly think that I have stripped the metal pinion gear since this is my first run after i had just put a heatsink on my motor. It looked fine then.

 

[jondilly1974]

Open it up and have a look. Maybe your mesh is too tight.

 

[BIGBOI]

yeh.