Honda crf250r 2012 Owner's Manual page 85

Piston/Piston Rings/Piston Pin
18. Remove the dowel pins (17), cylinder head
gasket (18) and cam chain guide (19).
NOTICE
Do not let the dowel pins and cam chain fall into
the crankcase.
(19)
(17)
(18)
(17) dowel pins (19) cam chain guide
(18) cylinder head gasket
78
Servicing Your Honda