GAS GAS Enduro Series, Workshop Manual

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Workshop manual
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SeRVICING aND RePaIRING THe eNGINe’S COmPONeNTS
Piston: ring end opening
- Insert a piston ring into the cylinder approximately 20 mm from the upper end.
- Using a thickness gauge, measure the distance between the ends of ring -A-
Ring end opening 200 cc: STD: 0.3 mm
Limit: 0.6 mm.
250 cc: STD: 0.4 mm
Limit: 0.7 mm.
300 cc: STD: 0.5 mm
Limit: 0.8 mm.
PIN
- Check the pin for jamming marks, grooves and overheating.
- Measure the pin bore with a micrometre at three different points.
Pin bore STD: 17.994 mm
Limit: 17.98 mm.
CYLINDER
Cylinder: internal measurement
- Check the cylinder for scratches, jamming marks, notches or breakages in the
intake and exhaust ports.
- Measure the cylinder bore approximately 20 mm from the upper end and at
different points to check for possible ovalling.
Cylinder bore 200 cc: STD: 62.50 mm
Limit: 62.60 mm.
250 cc: STD: 66.38 mm
Limit: 66.50 mm.
300 cc: STD: 71.99 mm
Limit: 72.10 mm.