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.
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
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
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.
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I received the Cam, But there were no instructions.
Banshee - Dipstick & Oil Plug Billet - Modquad
My 400ex has never sounded better. New tensioner, guides, and chain fixed the noise. Metal bottom end gasket was cool too, didn't rip while working on it.
Thank you for your positive review! We're glad to hear that the TRX400EX Cam Chain Tensioner & Wiseco Heavy Duty Cam Chain Kit was able to fix the ticking noise on your 400ex. We agree, these small maintenance steps can make a big difference in the overall performance and sound of your vehicle. We appreciate your feedback and hope to continue providing quality products for your ATV. Happy riding!
Well my mechanic said it was some good parts in the box. I'll let you know how the rebuild goes. Great I hope
I haven’t received them yet
Trevor, thank you for your 5 star review. We appreciate that. Rest assured I just checked your tracking info and UPS says they will arrive today between 1:30 & 3:00 pm. Your going to love the Lectron Carburetors!