This OS 0.75 oversize piston kit is designed specifically for Honda TRX 500 Foreman and Rubicon models from 2005 through 2011. By increasing the displacement and stabilizing compression, it helps restore strong top‑end power and smooth operation when you’re tackling tough trails or hard jobs on the farm. This replacement kit is built to deliver reliable, repeatable performance after a top‑end refresh, so you can ride or work with confidence.

Beyond simply replacing worn components, this OS oversize kit focuses on restoring compression consistency and durable power delivery under load. It’s a practical upgrade for riders who demand steady throttle response and long‑term reliability, offering a straightforward route back to clean starts, reduced oil blow‑by, and dependable performance in challenging conditions.

Comprehensive Vehicle Fitment

Product Specifications

OEM & Aftermarket Cross-Reference Information

What's Included

This kit includes the essential components for a complete top‑end refresh on your TRX500:

• Piston with OS 0.75 oversize
• Rings
• Piston Pin
• Circlips

Gaskets, seals, and cylinder components are not included unless specified.

Why Choose This Aftermarket Replacement?

• Direct-Fit Compatibility: Engineered to drop in with stock tolerances on the 2005–2011 TRX500 Foreman/Rubicon models.
• OEM Cross-Reference: Cross‑reference to Honda 13104-HP0-A00 for familiar fitment without OEM pricing.
• Premium Materials: Aluminum alloy designed for durability under repeated heat cycles and high load.
• Displacement Restoration: Oversize +0.75 mm helps reclaim lost compression and top‑end performance.
• Reliability in Tough Conditions: Built for reliable operation on trails and in farm work where debris and heat are constant factors.
• Cost‑Effective Rebuild: A practical alternative to OEM options with strong long‑term value for a durable top‑end refresh.

Installation Notes:

• Bore & Cylinder Prep: Inspect the cylinder bore for wear and out‑of‑round conditions; refurbish to the required oversize if needed and within service limits.
• Rings & Orientation: Lubricate rings and skirt surfaces, align orientation marks, and install with correct piston orientation relative to the crank.
• Ring Gaps: Set ring end gaps per the service manual; verify gaps after assembly to avoid contact with the top of the cylinder.
• Piston Pin & Circlips: Install the wrist pin with circlips and confirm the pin moves freely without binding.
• Lube & Break‑In: Apply assembly lube to moving parts, then follow a proper break‑in procedure to seat rings and optimize seal.
• Gaskets & Surfaces: Use new base/head gaskets and clean seating surfaces; do not reuse old gaskets to prevent leaks.

Why Upgrade?

Running a worn piston kit can lead to compression loss, oil consumption, and fluctuating power under load. Upgrading to this OS 0.75 oversize piston kit restores compression consistency and top‑end power, delivering dependable throttle response and engine reliability for demanding trails and farm work.