2006-2014 Honda FourTrax ATV TRX250 EX TRX250X Service Manual, Page 123Get this manual
CYLINDER HEADVALVECAMSHAFT Remove the timing hole cap from the left side of the rear crankcase cover
Turn the crankshaft counterclockwise and align the mark on the flywheel with the index mark on the crankcase coverMake sure the piston is at TDC (Top Dead Center) on the compression strokeThis position can be confirmed by checking for sla ck in the rocker armsIf there is no slack, it is because the piston is moving through the exhaust stroke to TDCRotate the crankshaft one full turn and match up the mark again