Suzuki FU150SC Manual page 32

3-25 ENGINE
CAM SPROCKET
CYLINDER
DISTORTION
CYLINDER BORE
PISTON AND PISTON PIN
DIAMETER
Using a micrometer, measure the piston outside diameter at
the place 15 mm from the skirt end as shown in Fig. If the
measurement is less than the limit, replace the piston.
Service Limit : 61.903 mm
Piston oversize : 0.5, 1.0 mm
09900-20203 : Micrometer (50-75 mm)
PISTON-CYLINDER CLEARANCE
As a result of the above measurement, if the piston to cylinder
clearance exceeds the following limit, overhaul the cylinder
and use an oversize piston, or replace both cylinder and piston.
Service Limit : 0.120 mm
PISTON RING-GROOVE CLEARANCE
Using a thickness gauge, measure the side clearance of the
1st and 2nd rings. If any of the clearances exceeds the limit,
replace both piston and piston rings.
Piston ring-groove clearance
1st : 0.18 mm
Service Limit
2nd: 0.145 mm
Piston ring groove width
1st : 1.01-1.03 mm
Standard 2nd: 1.01-1.03 mm
Oil : 2.01-2.03 mm
Piston ring thickness
Standard 1st and 2nd : 0.97-0.99 mm
09900-20803 : Thickness gauge
09900-20205 : Micrometer (0-25 mm)
NOTE :
Using a soft-metal scraper, decarbon the crown of the piston.
Clean the ring grooves similarly.
PISTON RING END GAP
Fit the ring in the cylinder, and measure each ring end gap
using a thickness gauge.
if any ring has an excess end gap, replace the ring.
Piston ring end gap
Service Limit 1st and 2nd : 0.34 mm
09900-20803 : Thickness gauge
ENGINE. 3-26
15 mm.