Honda 400EX 87mm Big Bore Kit + Wiseco Piston TRX400X XR400R 99–14

SKU 255042949515

🏁 Honda 400EX / 400X / XR400R 87mm Big Bore Kit – No Head or Case Mods Required

Fits 1999–2014 Honda TRX400EX / TRX400X / XR400R Models
Boost your Honda 400EX, 400X, or XR400R with this complete 87mm big bore kit that provides increased displacement, enhanced performance, and no major mods required.

📦 What’s Included:

• 87mm aftermarket big bore cylinder

• Wiseco or Wossner 87mm forged piston

• Nitrite coated piston rings

• Chrome wrist pin & circlips

• Cometic top-end gasket kit

• MLS big bore head gasket

• Talon TITANIUM cylinder head stud kit
  (LIFETIME WARRANTY*)

• Heavy-duty cam chain conversion

• NGK spark plug

• Stickers for your ride

💥 Key Features & Benefits:

• 🏎️ 87mm big bore for improved engine performance

• 💪 Forged piston offers strength and reliability

• 🛠️ Talon TITANIUM head stud kit ensures durability with a lifetime warranty

• ⛽ Runs on pump or race gas – great for both everyday use and racing

• 🔧 No case or head mods required – simple bolt-on installation

• ⚙️ Heavy-duty cam chain conversion for long-lasting engine performance

✅ Compatibility:

Fits all Honda 400EX, 400X, and XR400R models from 1999 to 2014:

• 1999–2008 Honda Sportrax 400 TRX400EX

• 2009–2014 Honda TRX400X

• Honda XR400R (all years)

🛡️ Warranty Information:

All components are brand new in original packaging, with the manufacturer’s warranty. We strongly recommend professional installation by an experienced mechanic. Warranty does not cover failure due to improper installation, tuning, break-in, or abuse. Returns and warranty claims require parts to be returned for inspection.