KYMCO K-XCT 300i Owner's Manual page 466

9. Brakes > Front Brake Caliper
Inspection
Inspect the pistons for wear and damage.
Measure the outside diameter of the piston with a micrometer
and compare the measurement with the specification. Replace
the pistons as needed.
Item
Brake caliper piston O.D.
Standard mm (in)
26.93 - 26.96 (1.0602 - 1.0614)
9-21
K- XCT 300i