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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

TRX400EX TRX 400EX 400X 88mm Big Bore Cylinder 426cc Top End Engine Rebuild Kit

by BPRATV
Sold out
Original price $486.10
Original price $486.10 - Original price $486.10
Original price $486.10
Current price $388.88
$388.88 - $388.88
Current price $388.88

12100-KCY-670, 12191-KCY-672, 13011-KCY-670, 13101-KCY-670, 90601-KA5-000, 13111-KCY-670, 12100-HN1-A70, 12191-KCY-672, 12251-HN1-003, 12391-KCY-671, 14560-KCW-851, 12100-HN1-A70, 12191-KCY-672, 13011-KCY-670, 12100-KCY-670, 4606M08800, C7826, 71016-4, 12191-KCY-673, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670,13111-KCY-670, 12251-HN1-003, 12209-KL4-005, 4040, 4606M08700, 4606M08800, 4667M08900, 808829, 808894, 8604DA, H0402027S, M2033

Honda TRX 400EX/X & XR400R 88mm Big Bore Cylinder Kit – Complete 426cc Top-End Rebuild with Premium Performance Parts


Maximize your Honda 400EX, 400X, or XR400R’s performance with the 88mm Big Bore Cylinder Kit – 426cc Top-End Rebuild, the ultimate upgrade for power-hungry riders. Precision-engineered for all models and years, this complete kit delivers unmatched reliability, durability, and aggressive performance gains without any case or head modifications.

What’s Included in the Kit?

  • 88mm heavy-duty big bore cylinder: Built to last under extreme conditions.
  • Premium forged piston kit (Wiseco or Wossner): Lightweight, high-strength performance for superior combustion.
  • Nitrite-coated piston rings, chrome wrist pin & circlips: Reliable sealing and durability.
  • Cometic big bore gasket kit: Comprehensive seal for maximum efficiency, including an MLS head gasket.
  • Talon TITANIUM cylinder head stud kit: Backed by a lifetime warranty, built to handle extreme pressure.
  • BPRATV heavy-duty cam chain: A perfect match for your high-performance build.

Key Features You'll Love:

Power & Versatility: Boost your engine’s displacement to an impressive 426cc. Runs flawlessly on both pump gas and race fuel.
DIY-Friendly: No need for case or head modifications – hassle-free installation.
Rider Confidence: Durable, high-quality components backed by a 1-Year Warranty for your peace of mind.
Proven Performance: Engineered by BPRATV, your go-to for the best parts, unbeatable performance, and incredible value.

Experience the adrenaline-pumping advantage of a high-performance 426cc engine on your next ride. Whether you’re shredding dunes or hitting the trails, this kit ensures your ATV dominates with power, reliability, and excitement.

Upgrade Today! BPRATV – The Best Parts. The Best Performance. The Best Price. BRAPPPP!

12100-KCY-670, 12191-KCY-672, 13011-KCY-670, 13101-KCY-670, 90601-KA5-000, 13111-KCY-670, 12100-HN1-A70, 12191-KCY-672, 12251-HN1-003, 12391-KCY-671, 14560-KCW-851, 12100-HN1-A70, 12191-KCY-672, 13011-KCY-670, 12100-KCY-670, 4606M08800, C7826, 71016-4, 12191-KCY-673, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670,13111-KCY-670, 12251-HN1-003, 12209-KL4-005, 4040, 4606M08700, 4606M08800, 4667M08900, 808829, 808894, 8604DA, H0402027S, M2033

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