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12_9f4606b5-b1e9-494d-a242-ac4b08a56d48 - Northline Parts

For Honda TRX400EX Big Bore Cylinder Piston Gasket Kit 1999-2008 89mm 440cc

Alligator_819_x_200_px - Northline Parts

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$115.99
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I reached out for some replacement head bolts and they responded quickly with a few questions and cautionary information and is sending me some bolts. Great customer service! Thanks

Edward H. — Verified customer

For Honda TRX400EX Big Bore Cylinder Piston Gasket Kit 1999-2008 89mm 440cc

Upgrade your ride with this high-performance big bore cylinder kit, designed to increase your engine's displacement to 440cc for significant gains in power and torque. This premium aftermarket kit provides everything you need for a top-end rebuild, ensuring your machine runs at its peak. Engineered for durability and a precise fit, it is an excellent choice for riders looking to enhance their off-road experience without the OEM price tag.

Key Features & Benefits

  • Boosts engine displacement to 440cc for improved performance
  • High-quality 89mm bore cylinder for reliable operation
  • Complete kit includes piston, rings, and necessary gaskets
  • Precision-engineered for a seamless installation
  • Durable construction designed to withstand rigorous trail riding
  • Cost-effective aftermarket alternative to original equipment

Compatible Models

  • 1999-2008 Honda TRX400EX
  • 2009-2014 Honda TRX400X

Product Specifications

  • Bore Size: 89mm
  • Displacement: 440cc
  • Part Type: Big Bore Cylinder Piston Gasket Kit
  • Condition: Brand New
  • Material: High-grade Aluminum and Steel components

Frequently Asked Questions

Is this an OEM part?
No, this is a high-quality aftermarket replacement part designed to meet or exceed the performance of the original equipment.

How do I confirm compatibility?
Please verify your vehicle's make, model, and year against the compatible models list provided. It is also recommended to check your specific engine requirements before purchase.


Important: This is an aftermarket replacement part sold by Northline Parts. It is not made by the original equipment manufacturer unless specifically stated. Brand names, model names, and part numbers are used only to identify compatibility. Please compare your original part, photos, and fitment details before ordering.

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Service was professional and easy to work with. They kept me updated on my order and recommended a different part when the one I originally picked wasn’t going to work. Everything showed up as expected and the process was smooth overall.

- Customer, Chris D.

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