Wiseco Forged Series Piston Kit with Gaskets - Honda TRX400EX/TRX400X/XR400R (1996-2014) - 89.00mm Bore (+4.00mm Big Bore) - 440cc - 4-Stroke
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Wiseco Forged Series Piston Kit with Gaskets - Honda 400 Platform - +4.00mm BIG BORE 440cc
Premium Wiseco Forged Series piston kit for Honda TRX400EX, TRX400X, and XR400R. +4.00mm BIG BORE (89.00mm) - increases displacement to 440cc!
⚠️ Big Bore Kit - Cylinder Sleeving & Boring Required
This piston is +4.00mm oversize. Requires LA Sleeve H5445 cylinder sleeve (sold separately) and boring to 89.00mm.
Kit Includes
- Forged Series Piston
- Ring Set
- Wrist Pin
- Wrist Pin Retainer Set
- Complete Gasket Kit
Key Features
- Forged Series - premium 2618 aluminum alloy
- 11.0:1 compression ratio
- 440cc displacement (up from 397cc = +43cc gain!)
- Cross-platform fitment (ATV + Off-Road motorcycle)
Piston Specifications
- Bore Size: 89.00 mm (+4.00mm Big Bore)
- Piston Diameter: 88.95 mm
- Stroke Length: 70.00 mm
- Compression Ratio: 11.0:1
- Material: 2618 Aluminum Alloy
- Skirt Coating: Non-Coated
Engine Specifications
- Displacement: 440cc (from 397cc)
- Engine Type: 4-Stroke
- Weight: 2.0 lbs
Fitment
- Honda TRX400X: 2009, 2012-2014
- Honda TRX400EX Sportrax: 2000-2008
- Honda TRX400EX FourTrax: 1999
- Honda XR400R: 1996-2004
📦 Shipping Information
In-stock items ship next business day. ModQuad parts dispatch Monday through Thursday.
Made-to-order and custom powder coat items show their lead time at the top of this page, right next to the truck icon. These are built fresh for you, so timing varies by brand and current backlog.
Need something by a specific date? Call us at 541-668-7503 before ordering and we will check stock and ETA on that exact part. We can often point you to an in-stock alternative from another distributor.
Questions? Contact us, we respond within 24 hours.
