Size C (54.21mm) Piston Kit for KTM 1994-2000 125 SX & 125 EXC STD Bore 54.25mm

Size C (54.21mm) Piston Kit for KTM

This Size C (54.21mm) piston kit is a replacement piston assembly for KTM 125 SX and 125 EXC motorcycles from 1994 to 2000, designed to restore engine compression and performance with a standard bore of 54.25mm.

Overview

This Size C (54.21mm) piston kit provides a direct-fit replacement for KTM 125 SX and 125 EXC models, delivering reliable power and durability for off-road riding. Manufactured to precise tolerances, this piston kit ensures consistent combustion and long service life, making it an ideal choice for rebuilding your KTM two-stroke engine.

Built For Performance

• Precision-machined from high-strength aluminum alloy for reduced weight and improved thermal conductivity
• Includes piston rings, wrist pin, and circlips for a complete top-end rebuild
• Size C (54.21mm) specification matches factory dimensions for KTM 125 engines
• Designed for a standard bore of 54.25mm to maintain proper clearance
• Tested for durability under high-RPM motocross and enduro conditions

Fits These Machines

• for KTM 125 SX (1994-2000)
• for KTM 125 EXC (1994-2000)

On-The-Job Use

• Motocross racing on closed tracks
• Enduro and trail riding through rugged terrain
• Engine top-end rebuilds for restored performance
• Competition and recreational two-stroke maintenance

Specs At A Glance

Good To Know

Q: Does this piston kit include a wrist pin bearing? A: The kit includes the wrist pin and circlips but does not include a wrist pin bearing; you will need to reuse or replace the bearing separately based on your engine condition.

Q: Is this piston compatible with a Big Bore kit? A: This Size C piston is designed for standard 54.25mm bore only and should not be used with overbore or big bore cylinders unless specifically noted.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.