VESPA GTS Super 125 i.e. Service Station Manual page 18

Characteristics
- Measure the diameter of the bearings on the pis-
ton.
Characteristic
Standard diameter:
15 +0.006 + 0.001mm
- Calculate the piston pin coupling clearance.
N.B.
THE PIN HOUSINGS HAVE 2 LUBRICATION CHANNELS. FOR THIS REASON, MEASUREMENT
MUST BE MADE ACCORDING TO THE PISTON AXIS
Characteristic
Standard clearance:
0.001 - 0.010 mm
- Check that coating is free from flakes.
- Check that the head coupling surface is not worn
or misshapen.
Characteristic
Maximum allowable run-out:
0.001 over 0.05 mm
- Pistons and cylinders are classified into categories based on their diameter. The coupling is carried
out in pairs (A-A, B-B, C-C, D-D).
CHAR - 18
Vespa GTS Super 125 i.e.