KYMCO ADG5, Manual

Page: 131 / 426

XCITING 400i 3. Engine > Cylinders and Pistons
Measure the outside diameter of the piston at 9 mm up from the bottom
of the skirt at a 90° angle to the piston pin. Measure the piston with
vernier calipers or a micrometer. Check the piston for wear, damage,
and extreme discoloration.
Subtract the diameter of the piston from the maximum front to rear
diameter measurement of the cylinder to calculate the piston-to-
cylinder clearance. Replace the piston and cylinder as needed to
achieve a correct piston-to-cylinder clearance.
Item Standard (mm)
Piston-to-cylinder clearance 0.010 - 0.030
Measure the piston pin diameter with a micrometer. Measure the
piston pin bore diameter with vernier calipers or a small bore gauge.
Measuring at three different points for each. Replace the parts if any of
the specifications are not met.
Item Standard (mm)
Piston pin hole I.D. 20.002 - 15.008
Piston pin O.D. 19.994 - 20.000
Piston-to-piston pin clearance 0.002 - 0.014
3‐53