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OEM & Performance ATV, UTV & Dirt Bike Parts for Yamaha, Honda, Polaris, Can-Am & More — Shipped Fast from BPRATV
OEM & Performance ATV, UTV & Dirt Bike Parts for Yamaha, Honda, Polaris, Can-Am & More — Shipped Fast from BPRATV

Honda TRX400EX TRX 400EX 400X 440cc Big Bore Kit Wiseco Piston & Gasket 89mm Kit

by Wiseco
Save 33% Save 33%
Original price $521.31
Original price $521.31 - Original price $521.31
Original price $521.31
Current price $349.89
$349.89 - $349.89
Current price $349.89

4667M08900, 8604D400, 247612, M2033, 1043-2, M2008, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670, 13111-KCY-670, 12251-HN1-003, 12209-KL4-005, C7825, 808894, 822278, 4040, 4606M08700, C7826, H0402027S, 4606M08800, 4667M08900, 808829, M2033, 8604DA, 192258099805

🔥 Honda TRX400EX/TRX400X 440cc Big Bore Top‑End Kit – 89mm Wiseco + Cometic 🔥

🛠️ Product Overview

Give your Honda TRX400EX or TRX400X serious power with this complete 440cc 89mm big bore top‑end rebuild kit. Featuring a Wiseco forged piston and Cometic gasket set, it's ready for pump or race fuel and bolts right into your stock engine.

✅ What’s Included

  • BPRATV Aftermarket 89 mm Big Bore Cylinder – increases displacement to 440cc
  • Wiseco 11:1 Forged Piston Kit – includes piston, rings, pin, and clips
  • Cometic Top‑End Gasket Kit – includes MLS head gasket

🚚 Model Fitment

• Honda TRX400EX / TRX400X (1999–2014)

🏆 Why You’ll Love It

  • Bolt‑on upgrade: No machine work or modifications required
  • Displacement boost: 440cc big bore adds torque and mid‑range power
  • Premium components: Wiseco forged piston & Cometic MLS gasket
  • Fuel flexibility: Built for pump or race gas
  • New sealed packaging: Includes full manufacturer warranty

❓ Frequently Asked Questions

  • Q: Is any machine work required?
    A: No – designed for easy drop‑in install.
  • Q: What fuel is required?
    A: Works great with pump gas; race gas optional.
  • Q: Is piston choice customizable?
    A: Standard Wiseco; message us if you prefer alternatives.

🌟 Why Buy from BPRATV?

BPRATV – The Best Parts. The Best Performance. The Best Price.
Comes new in‑box, backed by manufacturer warranty and our expert support.
BRAPPPPPPPPPP!

Build your 400EX/400X into a 440cc beast—get your kit today! 


🏁Upgrade to big bore power now—bolt-on performance awaits! 🏁

© BPRATV LLC

4667M08900, 8604D400, 247612, M2033, 1043-2, M2008, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670, 13111-KCY-670, 12251-HN1-003, 12209-KL4-005, C7825, 808894, 822278, 4040, 4606M08700, C7826, H0402027S, 4606M08800, 4667M08900, 808829, M2033, 8604DA, 192258099805

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