Namura Size B (66.35mm) Piston Kit for KTM 250 SX MXC & EXC Standard Bore 66.4mm

Namura Size B (66.35mm) Piston Kit for KTM

This Size B (66.35mm) piston kit from Namura fits KTM 250 SX, MXC, and EXC models with a standard bore of 66.4mm.

Overview

The Namura Size B piston kit is a high-quality replacement for KTM 250 two-stroke engines, sized at 66.35mm for standard bore applications. It is designed for KTM 250 SX, MXC, and EXC models requiring a direct-fit piston. This kit includes all necessary components for a complete piston replacement.

Built For Performance

• Premium aluminum alloy construction for lightweight strength
• Size B (66.35mm) for standard bore 66.4mm cylinders
• Includes piston rings, wrist pin, and circlips
• Engineered for high-revving two-stroke KTM engines
• Rigorous quality control from Namura for reliable performance

Fits These Machines

• for KTM 250 SX
• for KTM 250 MXC
• for KTM 250 EXC

On-The-Job Use

• Rebuilding KTM 250 two-stroke engines for motocross and enduro
• Restoring compression in high-mileage 250 SX/MXC/EXC machines
• Performance rebuilds for off-road racing and trail riding

Specs At A Glance

Good To Know

Q: What does Size B mean in a piston kit? A: Size B indicates a slight oversize compared to standard, typically used to compensate for minor cylinder wear while staying close to stock bore dimensions.

Q: Does this kit fit all years of KTM 250 SX? A: This kit is designed for a range of model years, but always verify your cylinder bore and piston clearance with your specific engine serial number before installation.

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