1985-1986 Honda Fourtrax 125 TRX125 Shop Manual, Page 238Get this manual
TROUBLESHOOTING 10Remove oil level gauge and check
OIL LEVElINCORRECT (1) Oil level too high
(2) Oillellel too low (3) Contaminated oil
oit levelCORRECT
11 Remove cylinder head cover and
inspect for proper lubricationVALVE TRAIN LUBRICATED
VALVE TRAIN NOT-_ (1) Clogged oil passage LUBRICATED PROPERLY (2) Clogged oil control orifice
PROPERLY
12Check if engine overheats,
NOT OVERHEATED
OVERHEATED (1) Excessive carbon build-up
in combustion chamber
(2) Use of improper quality fuel (3) Clutch slipping