Wiseco WPC131B Complete Bottom End Rebuild Kit 2005-2008 Honda TRX400EX

The Wiseco WPC131B Complete Bottom End Rebuild Kit delivers everything needed to perform a thorough, professional-grade bottom end rebuild on 2005–2008 Honda TRX400EX ATVs. Built around a double-forged crankshaft assembly, this kit provides strength, reliability, and dimensional consistency that cast crankshafts simply cannot match. Wiseco engineers design each crankshaft to meet or exceed OEM tolerances, giving your build the strongest possible foundation.

Forged Crankshaft & Connecting Rod Advantages:

• Double-forged connecting rod manufactured from dedicated forgings for superior grain flow, strength, and durability
• Shot-peened rods eliminate residual stress for longer service life under high-load, high-RPM conditions
• Strategically located oil slots maximize lower rod oiling and extend bearing life
• Coated bronze thrust washers feature a dimpled design to improve oil retention and reduce stress between the connecting rod, washer, and crank web
• Double-drilled small ends provide the piston pin with extra lubrication and cooling, reducing thermal distortion at the top end
• Top end of rod is bushed for oil retention and to eliminate pin galling
• Bottom end rod bores are case hardened to 58–62 RC to optimize the bearing running surface

Premium Bearings & Hardware:

• Main bearings manufactured to the highest quality standards, case hardened for maximum life and smooth operation at high RPMs
• Corrosion-resistant surface treatment protects against corrosion and pitting during long-term use or storage
• Crank pin bearings made from hot-rolled steel, case hardened to 58–62 RC to extend assembly life
• Caged needle roller bearings engineered for maximum possible RPM capability

Complete Bottom End Gasket Kit Included:

• All applicable bearings included for a complete rebuild
• Full bottom end gasket kit made from premium materials that meet or exceed OEM specifications
• Provides an exceptional seal across all critical mating surfaces

The Wiseco WPC131B is the all-in-one solution for ATV enthusiasts and professional mechanics looking to restore bottom end performance and reliability. With forged components, precision tolerances, and a comprehensive gasket set, this kit ensures your rebuild is done right the first time.