2006-2012 Honda TRX90 TRX90EX/X Service Manual, Page 281Get this manual
18TROUBLESHOOTING
ENGINE DOES NOT START OR IS HARD TO START 18-2 ENGINE LACKS POWER 18-3
POOR PERFORMANCE AT LOW AND IDLE SPEED 18-5 POOR PERFORMANCE AT HIGH SPEED 18-6 POOR HANDLING 18-6