Yamaha YB50 Service Manual page 86

ASSEMBLY AND ADJUSTMENT OF ENGINE
PISTON, CYLINDER AND CYLINDER HEAD
Carburettor gasket
Reed valve
Gasket
Cylinder head
Cylinder head gasket
Cylinder
CLEARANCE FROM PISTON TO
CYLINDER:
0.034 ~ 0.047 mm
Limit: 0.1 mm
BETWEEN ENDS (INSTALLED):
Top ring
0.15 ~ 0.35 mm
Limit:
0.60 mm
Second ring
0.15 ~ 0.35 mm
Limit:
0.60 mm
LATERAL CLEARANCE:
Top ring
0.03 ~ 0.05 mm
Limit
0.10 mm
Second ring
0.03 ~ 0.05 mm
Limit
0.10 mm
Cylinder seal
Piston rings
Piston
k
Piston pin
10
k
Circlips
11
k
Bearing
12
SPARK PLUG
MANUFACTURER/TYPE:
NKG/BR7HS
GAP BETWEEN ELECTRODES
0.06 ~ 0.7 mm
4-35
MOT