I’m looking for suggestions on gearing a Trinity Monster Max 13.5 in a B64D. It will be used on a medium/large clay track (OCRC), which has medium/high traction. And also gearing on a small outdoor dirt track which has a hard, bumpy surface with a little dust on top.

Also gearing suggestions with that motor in a B6 on the same type of tracks.

Thanks!

pretty good resource here:
Team Associated B64 & B64D Setup Sheets

Check out Curt Wenger's setup for OCRC:
Team Associated B64D - Kurt Wenger - OCRC - 11.05.2016

He's got 24/76... I would start there if it were me.

maybe not the best advice since they don't make a 76t spur...

i'm currently geared at 26/78 on a small indoor clay track.

AE suggests starting at 78/28. I'm at 78/30 running high grip astro-turf. tekin rs pro esc (blinkey mode), Orca 13.5 motor, vented body and 30mm cooling fan. Comes off track at 164f after 6 minutes.