Yamaha Banshee 421cc Serval Cub Big Bore Top End Kit – 4mm Stroker (NEW)

Turn your Banshee into a monster with this complete 421cc Serval Cub big bore top end rebuild kit. Designed for a 4mm stroker crank (115mm rods), this kit is packed with high-end components like titanium studs, billet domes, and coated pistons. No case mods needed—just bolt on and rip. ✅ What’s Included: CPI Serval Cub Cylinder – 68mm bore x 58mm stroke (421cc) Wiseco or Wossner Forged Pistons – 68mm Blaster-style Nitride Coated Rings, Chrome Wristpins, Circlips Billet Pump Gas Cool Head Domes One-Piece Cub Base Gasket Intake Gaskets Cool Head O-Ring Kit SKF Wrist Pin Bearings Titanium Extended Cylinder Studs (no extenders needed) Titanium Head Stud Kit w/ ARP 12pt Nuts – Lifetime Warranty Water Jacket Plugs 📦 Fitment: Fits Yamaha Banshee 350 using a 4mm stroker crank (115mm rods) No case modifications required Compatible with stock or aftermarket bottom ends built for 421cc Cub/Serval configurations 🛡️ Warranty Info: CPI Cylinder Warranty: We’ll fix or replace any failed Cub cylinder not caused by misuse, break-in error, or improper installation. Titanium Stud Warranty: Lifetime replacement if a stud fails during use (not installation). Studs must be returned for inspection. General Warranty: Parts must be installed and tuned by a qualified, experienced builder. Warranty is voided by incorrect tuning, break-in, or assembly.