Restore engine compression and crisp throttle response with this STD bore Piston Ring Kit designed for the TRX 450 Foreman 1998-2004 4x4 ATVs. The kit targets FM/FE/ES/S models within that window, providing a straightforward top-end rebuild path to bring power and reliability back to the trail or farm. With a true standard bore, it offers a simple, direct replacement that seals cleanly against the cylinder for dependable combustion.

This aftermarket replacement focuses on restoring proper ring seal under demanding conditions, addressing common wear symptoms like reduced compression, oil consumption, and sluggish response. Built to endure rugged use and heat cycling, it delivers a cost-effective alternative to OEM parts without sacrificing performance or durability on tough terrain.

Comprehensive Vehicle Fitment

Product Specifications

OEM & Aftermarket Cross-Reference Information

What's Included

This kit includes the essential piston rings designed for a standard 90 mm bore TRX450 engine.

• Top Compression Ring
• Second Compression Ring
• Oil Ring

Note: The kit does not include the piston, wrist pin, circlips, or gaskets.

Why Choose This Aftermarket Replacement?

• Direct-Fit Compatibility: Precisely matched to TRX450 Foreman models from 1998-2004 (FM/FE/ES/S) with standard bore.
• OEM Cross-Reference: Backed by Honda OEM references 13010-HN0-A01 / 13010-HN0-A02, with a trusted aftermarket alternative.
• Premium Materials: Chrome-faced top ring and durable cast-iron rings designed to resist wear and maintain seal integrity.
• Performance Restoration: Restores compression, throttle response, and combustion efficiency for rugged terrain.
• Cost-Effective: A budget-friendly option that preserves reliability without the OEM price tag.
• Reliability in Harsh Conditions: Built to handle trail and farm duties where heat, dust, and heavy loads are common.

Installation Notes:

• Verify Bore Size: Confirm a 90.0 mm standard bore before installation; if the cylinder has been bored oversize, you’ll need an oversize kit.
• End-Gap Verification: Check ring end gaps against OEM specifications for a 90 mm cylinder using a feeler gauge.
• Cylinder Prep: Thoroughly clean the cylinder bore and remove any nicks or burrs; hone as required per OEM guidelines.
• Lubrication: Lubricate rings and cylinder walls with clean engine oil prior to installation.
• Ordering Clarification: This kit includes only rings; pistons, wrist pins, circlips, and gaskets are not included—plan install accordingly.
• Ring Handling: Use a proper ring expander to avoid damaging or warping rings during placement; install in the correct order (top ring, second ring, oil ring).

Why Upgrade?

Running worn rings in this 90 mm bore can lead to a dramatic drop in compression, increased oil consumption, and sluggish response in demanding terrain. Replacing with this STD bore kit restores sealing efficiency and enables reliable, consistent combustion, helping you ride with confidence on trails or across the farm.