2006-2009 Honda TRX250EX/TRX250X Service Manual, Page 145Get this manual
CYLINDER HEADIVALVECAMSHAFT Measure each follower I.DSERVICE LIMIT: 22.54 mm (0.887 in) Subtract each follower .0 from the corresponding bore 1.0to obtain the clearanceSERVICE LIMIT: 0.07 mm (0.003 in)
CAM CHAIN TENSIONER ARM Check the slipper surface of the tensioner arm fo wear or damage
CAM CHAIN TENSIONER LIFTER Check the lifter operation as followsThe tensianer shaft should not go into the body when it is pushedWhen the stopper block is pressed inthe tensioner shaft should be pushed into the bodyThe shaft spring out of the body when the stopper block is released