Piston To Cylinder Clearance; Conrod; Piston And Piston Ring - Suzuki RM250 Owner's Service Manual

6-8 CYLINDER, PISTON AND EXHAUST VALVE
• Inspect for cylinder distortion with the thickness gauge.
 Cylinder distortion: Service limit: 0.05 mm (0.002 in)
 09900-20803: Thickness gauge
• Measure the cylinder bore for wear with the cylinder gauge at
20 mm (0.79 in) from the top surface.
NOTE:
The cylinder bore must be measured perpendicular to the crank-
shaft axis direction.
 Cylinder bore
Standard: 66.400 – 66.415 mm (2.6142 – 2.6148 in)
 09900-20508: Cylinder gauge set

PISTON TO CYLINDER CLEARANCE

 Piston to cylinder clearance:
Standard: 0.045 – 0.055 mm (0.0018 – 0.0022 in)
Service limit: 0.120 mm (0.0047 in)

CONROD

• Measure the conrod small end bore. (10-8)

PISTON AND PISTON RING

• Remove carbon deposits from the piston.
• Inspect the piston for wear, scratches and damage.
• Measure the piston outer diameter at 19 mm (0.75 in) from
the skirt end.
 Piston diam
Service limit: 66.280 mm (2.6100 in)
 09900-20203: Micrometer (50 – 75 mm)
• Measure the piston pin bore and piston pin diameter.
 Piston pin bore
Service limit: 18.030 mm (0.7098 in)
 Piston pin O.D
Service limit: 17.980 mm (0.7079 in)
 09900-20605: Dial caliper
09900-20205: Micrometer
20 mm
(0.79 in)
19 mm
(0.75 in)