1998-2001 Honda Fourtrax Foreman TRX450S, TRX450ES Factory Service Manual, Page 409Get this manual
TROUBLESHOOTING
POOR PERFORI ANCE AT HIGH SPEED M
Possible cause 1Discon neclfuel tube at carburetor-Fuel flow
Fue flows freely
Clogged fuel fine Clogged fuel fill cap breather
F.aulty fuel valve Clogged fuel filter
+ 2Remove the carbu retor and check-for clogging
Clogged- I Jr
Correct
4Check Ign ition tim ing Incorrect- Faulty ignition control module -Faulty igniti on pulse generator
Camshaft not installed properly
Correct
6Check va lve spring
Faulty spring