ProX Piston Kit for Suzuki RM250 and Yamaha YZ250/YZ250X (01.2321.A)

The PROX 01.2321.A Piston Kit is designed as an OEM replacement for select Suzuki RM250 and Yamaha YZ250/YZ250X applications. Manufactured in Japan, this kit delivers dependable fitment and consistent performance for motocross, off-road, and high-performance two-stroke engine maintenance. The piston is engineered for riders and technicians seeking a replacement component built to meet demanding OEM-level requirements.
Cast from a high-silicon-content aluminum alloy, the PROX piston meets or exceeds OEM specifications for strength, durability, and dimensional stability. The alloy helps the piston withstand the heat and operating demands of performance two-stroke engines, while CNC machining ensures extremely close tolerances for accurate installation and reliable operation. Its 2.61-inch piston diameter is suited to the specified applications and should be matched with the correct engine and cylinder specifications before installation.
This complete PROX piston kit includes the piston, ring kit, wrist pin, and circlips, providing the primary components needed for a piston replacement service. Supplied components help simplify engine rebuilding and support proper assembly when installed according to the motorcycle manufacturer’s service procedures. Verify application details, cylinder condition, and required clearances before installation to ensure the best results.
Choose the PROX 01.2321.A when replacing worn or damaged piston components in a compatible Suzuki RM250 or Yamaha YZ250/YZ250X engine. With Japanese manufacturing, OEM-focused design, and precision CNC machining, this kit is a practical solution for restoring compression, supporting efficient engine operation, and maintaining reliable two-stroke performance.

Features:

• OEM replacement design for select Suzuki RM250 and Yamaha YZ250/YZ250X applications

• Manufactured in Japan for consistent quality and dependable fitment

• Cast from high-silicon-content aluminum alloy to meet or exceed OEM specifications

• CNC-machined to extremely close tolerances for precision installation

• Kit includes piston, ring kit, wrist pin, and circlips

• Piston diameter: 2.61 inches

Ships from Parts Unlimited.