1986-1989 Honda TRX250 FourTrax 250R Service Manual, Page 215Get this manual
TROUBLESHOOTING
POOR PERFORMANCE AT HIGH SPEEDS
CHECK CONDITION INCORRECT PROBABLE CAUSE Faulty COl unit Faulty pulse generator
1Check ignition timing
CORRECT
2DJconnect fuel tube at carburetor
FUEL FLOWS OUT FREELY
FUEL FLOW RESTRICTED
Lack of fuel in tank Clogged fuel line Clogged fuel tan breather tube Clogged fuel valve Clogged fuel strainer Not cleaned frequently enough