1998 Foreman 450 ES 4X4 runs excellent except that if you run it hard it doesn't shift gears?

Question

if you try to shift with very high rev on the engine it doesn't shift yet it stays in the lower gear dashes ----- show in the gear indicator and it won't shift at all I have to shut it off turn it back on shift to neutral and start over sometimes it won't shift back to neutral so I carry a 12 mm wrench with me to get it back to neutral

Answer 1

With engine off, rock the quad forward and back while shifting gears.
If it has shifting problems, then the engine will have to be dis-assembled to check and repair the transmission.
Start and ride the quad without touching the electronic shift (only use the shift lever).
If you still have a problem, then the trani will have to be checked.
If the problem doesn't start happening until you use the electronic shift, could be -
Shift control motor.
Control motor shift linkage (remove the front cover).
Clutch cam needs adjusting, or is defective.
Go to - Crankcase Cover, Fr.
http://www.bikebandit.com/partsbandit/OEM-Parts-Nav.asp
#16 is the adjuster screw
Loosen it's lock nut # 36
Turn the screw until you feel a little resistance (I forget which way. Turn it left a turn, bring it back and then turn it right a turn. Keep going back and forth in equal increments until you feel resistance).
Then loosen it 1/4 turn and tighten the lock nut.

Answer 2

What does your oil look like? If it only happens after it warms up and your running it, sounds like you need to change the oil.