Honda HHT25S Manual page 39

MAINTENANCE
8. VALVE CLEARANCE ADJUSTMENT
Valve clearance inspection and adjustment must be performed with the
engine cold.
1. Loosen the 5 mm hex bolt and remove the top cover.
2. Remove the two 5 x 12 mm hex bolts from the head cover.
Engine oil can leak out when removing the head cover. Catch the
leaking oil with a suitable material and wipe up the area
immediately.
3. Set the piston at top dead center of the compression stroke by
positioning the " " mark on the cam pulley up and the alignment
marks even with the head cover mating surface.
4. Insert a feeler gauge between the rocker arm and valve to measure
the valve clearance.
Standard valve
clearance
5. If adjustment is necessary:
a. Loosen the adjusting screw lock nut and turn the adjusting screw
in or out. To increase valve clearance, turn the screw out. To
decrease valve clearance, turn the screw in.
b. Hold the adjusting screw with the tappet adjusting wrench, and
tighten the lock nut to the specified torque.
TORQUE: 4.9 N•m (0.50 kg•m, 43 in•lb)
c. Recheck the valve clearance.
6. Install the head cover and tighten the 5 x 12 mm socket bolts.
7. Install the top cover.
3-10
IN 0.08 ± 0.02 mm
EX 0.11 ± 0.02 mm
5 mm
TOP COVER
BOLT
CYLINDER
HEAD COVER
ENGINE
ASSEMBLY
ALIGNMENT MARK
ALIGNMENT MARK
FEELER GAUGE
HHT25S•HHT35S
TOP COVER
5 x 12 mm
SOCKET
BOLT (2)
CAM PULLEY
ADJUST
SCREW
LOCK NUT