gearing advise for a mate please guys

[blitzboy]

hi all my buddy just bought one of these buggies and hes changed the motor to a brushed 19 turn check point and added a lipos 500 mah 2oc on the standard speedo which is an ai reverse , 18 turn limit , just wanted to ask what gearing to gfo on ,, running it on 24 tooth and the motor and speedo are getting warm ,, the speedo should be ok with this motor and lipo so just need advise on the gearing

any advise on gearing would be apprecaited guys