2007-2009 Kawasaki KFX50 service manual, Page 188Get this manual
13REAR WHEELSWING ARMHYDRAULIC BRAKE Remove the four bolts and rear axle hubAxle Hub
Bolts INSPECTION Replace the rear axle if it is scratched (excessively) or damageReplace it if splines and threads of the rear axle are wear or damage
Rear Axle Measure the rear axle run outService limit: less than 1.5 mm (0.06 in) Replace it if it is out of specificationDo not attempt to straighten bent axle