all the hb's at my local track shred the gears in their diffs even though they're harden steel, they don't mesh correctly. i'll just do what the nitro guys do and put kyosho gears in.

I don't know what kyosho gears? the kyosho gears i know with a 4mm hole are from aluminum.

Shimming is the key..

i would think hotbodies diffs are stronger then kyosho ones.
indeed shimming is key to bullet proof diffs.
the kyosho 43/10 R&P sets are knowen to strip.
so i got the hotbodies coming my way.

diff gears only. i will only change the diff gears inside the diff cup. r+p are ok. go to truggyracers.com and check the hb forum. i know you have been there serum, i saw your conversion.