2006-2009 Honda TRX680 (TRX 680 FA-FGA) Factory Service Manual, Page 88Get this manual
MAINTENANCE Remove the four bolts, intake and exhaust valve adjustinq hole CClpS
Rotate the cra nkshaft using the reco il starter knob and align the "I" mark on the flywhee with the index ma rk on the rear crank case coverM ake sure the isto is at TOC {Top Dead Center! on the co mpression strokeTh is positio can be obtained by con firm ing that there is slack in the roc ker arm If the re is no slack, it is because he piston is moving through the exha ust stro ke to TDCRotate the crankshaft one fuJi turn and atch up the "T" mark again