Gearing dex210

[Chop chop]

Guys

Running a dex210 on astro with a speed passion reventon pro and sp 7.5 motor. Ran great all night but cut out at the end of the last race and motor seemed v.hot. Left for 5 mins and run again ok as a test

I am running 81spur and 26 pinion, wondered what you guys run and whether I am over gearing perhaps. All settings are standard on esc new from box

Help welcomed as normal