2006-2009 Honda TRX680 (TRX 680 FA-FGA) Factory Service Manual, Page 459Get this manual
FRONT DRIVING MECHANISM Turn he mm nut and check the pinion gear turn sm oothly and quietly without bindingIf the pinion gear does not turn smooth ly quietly,
the pinion qe ar, ring ge andor bea ring may be
damaged or aul ty They must be checked afte dis assembly; rep lace hem if necessary
BACKLASH INSPECTION
Ho ld Ihe pinion gear with th nu t
Set the differentia case into jig or vise with soft jawsInstall Ihe differential inspect io 1001 int he ri ht
side of the diffe rential