5-44 ENGINE TOP END
Install the front cylinder in the same way.
Position the front piston at TDC.
Tighten the cylinder nuts temporarily (These nuts are
tightened to the specified torque after rocker case instal-
Since there is a difference in cylinder wear in different di-
rections, take a side-to-side and a front-to-back measure-
ment at each of the three locations (total of six measure-
ments) shown in the figure.
If any of the cylinder inside diameter measurements ex-
ceeds the service limit, replace the cylinder.
10 mm (0.394 in.)[A]
70 mm (2.756 in.)[B]
20 mm (0.787 in.)[C]
Cylinder Inside Diameter
Measure the outside diameter [A] of each piston 5 mm
[B] up from the bottom of the piston at a right angle to the
direction of the piston pin.
If the measurement is under service limit, replace the pis-
Subtract the piston diameter from the cylinder inside di-
ameter to get the piston/cylinder clearance.
0.043 ~ 0.070 mm (0.00169 ~ 0.00276 in.)
If the piston/cylinder clearance is less than the specified
range, use a smaller piston made within the standard di-
ameter or increase the cylinder inside diameter within the
standard diameter by honing.
If the piston/cylinder clearance is greater than specified
range, use a larger piston made within the standard di-
If only a piston is replaced, the clearance may exceed
the standard slightly. But it must not to be less than the
minimum of the clearance in order to avoid piston seizure.
102.000 ~ 102.012 mm
(4.015748 ~ 4.01622 in.), and
less than 0.01 mm (0.0004 in.)
difference between any two
102.10 mm (4.01969 in.) or 0.05 mm
(0.002 in.) difference between any
101.942 ~ 101.957 mm
(4.013457 ~ 4.014047 in.)
101.79 mm (4.00748 in.)