2006-2014 Honda FourTrax ATV TRX250 EX TRX250X Service Manual, Page 295Get this manual
REAR DRIVING MECHANISM INSPECTION DRIVE SHAFT Check the shaft spring for fatigue or damageCheck the splines of the drive shaft for wear or damageIf the splines are damaged, check the pinion and universal joint splines alsoFor universal joint removalinstallation, see page 147 "Swingarm"SPRING SPLINES
FINAL DRIVE GEAR Temporarily install the drive shaft into the final gear caseTurn the drive shaft and check that the gears turn smoothly and quietly without bindingIf the gears do not turn smoothly and quietly, the gears andor bearing may be damaged or faultyThey must be checked after disassembly; replace them if necessary