Yamaha F100B - Checking the Piston Clearance; Checking the Piston Rings

POWR
Power unit
5-41
60C5D11
Checking the piston clearance
1. Rebore the cylinder or replace the piston
and piston rings as a set, or the cylinder
body, or all parts if out of specification.
Checking the piston rings
1. Check the piston ring dimensions of B
and T. Replace if out of specification.
2. Level the piston ring
1
in the cylinder
with the piston crown.
3. Check the piston ring end gap
e
at the
specified measuring point. Replace if out
of specification.
Piston clearance:
0.07–0.08 mm (0.0028–0.0031 in)
Piston ring dimensions:
Top ring
a
:
B: 1.17–1.19 mm
(0.0461–0.0468 in)
T: 2.8–3.0 mm (0.111–0.118 in)
Second ring
b
:
B: 1.47–1.49 mm
(0.0579–0.0586 in)
T: 3.00–3.20 mm
(0.1182–0.1259 in)
Oil ring
c
:
B: 2.38–2.48 mm
(0.0938–0.0976 in)
T: 2.40 mm (0.0945 in)
Measuring point
d
: 20 mm (0.8 in)
Piston ring end gap
e
:
Top ring:
0.15–0.35 mm
(0.0060–0.0137 in)
Second ring:
0.70–0.90 mm
(0.0276–0.0354 in)
Oil ring:
0.20–0.70 mm
(0.0079–0.0275 in)
S60C5850