2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 519Get this manual
TROUBLESHOOTING
POOR PERFORMANCE AT LOW AND IDLE SPEED
1Pilot Screw Inspection Check the carburetor pilot screw adjustmentIs the adjustment correct? YES NOGO TO STEP 3('04'05) GO TO STEP 2(After '05)See page 7-23('04-'05) See page 8-24(After '05)
2Accelerator Pump Inspection (After '05) Check accelerator pump for operationIs the accelerator pump operation correct? YES NOFaulty accelerator pumpGO TO STEP 3