Honda TRX 400 EX Piston Kit - Vertex Pistons - +0.50mm Oversized Cast Replica - `99-`08 is a direct-fit replacement kit for the Honda TRX400EX (1999–2008). This +0.50mm oversized cast replica piston kit is intended for use when rebore or replacement is required to restore proper compression.

The kit includes piston, rings, wrist pin and circlips for a complete install. Exact-fit A, B or C pistons allow selection to match your cylinder bore and help reduce blow-by and oil consumption. Skirts are treated with a molybdenum disulfide (MoS2) coating to promote faster break-in and improved skirt life. The piston is heat treated using a T-5 hardening and tempering cycle for consistent material properties. Designed for enthusiasts seeking reliable, OEM-style replacement components without speculative claims, this kit follows the original specifications for the TRX 400 EX 400cc engine.

Features

• +0.50mm oversized cast replica piston for 1999–2008 TRX400EX
• Includes piston, rings, wrist pin and circlips
• Exact-fit A, B or C piston options to match bore
• Skirt MoS2 coating for reduced break-in wear
• T-5 heat treated and tempered for strength

If you have questions or need help confirming fitment, call us directly — we’re happy to assist. We offer installation and customization services at our two locations in Austin, Texas and the Los Angeles, California area: 512-982-9393 (TX), 562-981-6800 (CA). If you are considering purchasing multiple items, please contact us for shipping discounts. We install on premises at both locations.

CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov