Periodic Maintenance Procedures
Check the valve clearance when the pistons are at TDC.
The pistons are numbered beginning with the engine left
Using a wrench [A] on the crankshaft rotation bolt, turn
the crankshaft clockwise until the "1|T" mark on the timing
rotor is aligned with the notch [B] in the edge of the upper
hole in the clutch cover for #1 piston and "2|T" mark for
1|T Mark [A]
2|T Mark [B]
Hole [C] of Upper Cap
Notch [D] in Edge of Upper Hole
Measure the valve clearance of the valves for which the
cam are turned away from each other.
Using the thickness gauge [A], measure the valve clear-
ance between cam and valve lifter.
Exhaust 0.22 ∼ 0.31 mm (0.0087 ∼ 0.0122 in.)
0.15 ∼ 0.21 mm (0.0059 ∼ 0.0083 in.)
Each piston has two inlet and two exhaust valves. Mea-
sure these two inlet or exhaust valves at the same crank-
Valve Clearance Measuring Position
#1 Piston TDC at End of Compression Stroke →
Inlet valve clearances of #1 piston, and
Exhaust valve clearances of #1 piston
Check the valve clearance using this method only.
Checking the clearance at any other cam position may
result in improper valve clearance.
PERIODIC MAINTENANCE 2-21