Honda HHT25S Manual page 100

HHT25S•HHT35S
VALVE SPRING FREE LENGTH
Measure the free length of the valve spring.
Standard
HHT25S 20.66 mm (0.8134 in)
HHT35S 21.77 mm (0.8570 in)
VALVE FACE/STEM O.D.
Inspect each valve for pitting or wear irregularities. Inspect each valve
stem for bending or abnormal stem wear. Replace the valve if
necessary. Measure and record each valve stem O.D.
3.470 ~ 3.485 mm
IN (0.1366 ~ 0.1372 in)
3.435 ~ 3.450 mm
EX
(0.1352 ~ 0.1358 in)
Replace the valves if their O.D. is smaller than the service limit.
VALVE GUIDE I.D.
Measure and record each valve guide I.D.
Standard
3.500 ~ 3.518 mm
(0.1378 ~ 0.1385 in)
Replace the cylinder block if the measurement exceeds the service
limit.
VALVE STEM-TO-GUIDE CLEARANCE
Subtract each valve stem O.D. from the corresponding guide I.D. to
obtain the stem-to-guide clearance.
Standard
0.0150 ~ 0.0480 mm
IN (0.0006 ~ 0.0019 in)
0.0500 ~ 0.0830 mm
EX
(0.0020 ~ 0.0033 in)
CRANKSHAFT / PISTON / VALVES / CYLINDER BLOCK
Service limit
20.00 mm (0.7874 in)
21.00 mm (0.8268 in)
Standard Service limit
3.400 mm
(0.1339 in)
3.380 mm
(0.1331 in)
Service limit
3.560 mm
(0.1402 in)
Service limit
0.0980 mm
(0.0039 in)
0.1200 mm
(0.0047 in)
VALVE FACE
9-9