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CYLINDER FULL KIT 85mm YAMAHA YZ 250F 2024, ATHENA P400485100106 304CC BIG BORE, (Piston included)

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Athena big bore cylinder full kit, part reference P400485100106. This kit increases displacement via an 85 mm bore to 304 cc. Supplied with high-grade cylinder, forged piston with pin and rings, complete gasket set, and a pre-mapped GET Boost module that installs without ECU or wiring modifications. Features include a big bore cylinder kit Ø 85 mm, 304 cc to increase performance. Cylinder manufactured from high-silicon aluminium alloy with an oversized steel liner. Steel liner fused using co-casting process for heat transfer and combustion sealing. Forged piston, CNC-machined. Molybdenum disulphide piston coating to reduce friction. DLC-coated piston pin for hardness and durability. Piston rings and pin included. Complete gasket set included. MLS head gasket, laser-cut stainless steel. GET Boost electronic module included, pre-calibrated for this kit. GET Boost installs without ECU or wiring modifications. Dedicated harness connects to injector and throttle body. Pre-mapped to suit the new cylinder configuration. Piston included. Athena part reference: P400485100106. Specifications: Bore diameter: 85.00 mm, Displacement: 304.00 cc.

Specifications
SKU
56-K250.85.KIT3
Brand
Athena
Availability
In Stock (1)
SKU
56-K250.85.KIT3
Brand
Athena
Availability
In Stock (1)
Delivery2–4 business days
14-Day ReturnsHassle-free
Easy CheckoutCard friendly
Product details

FULL DESCRIPTION

Athena Big Bore Cylinder Full Kit - 304cc for Yamaha YZ250F

Enhance the performance of your Yamaha YZ250F with this Athena Big Bore Cylinder Full Kit. This comprehensive kit increases displacement to 304cc through an 85mm bore, delivering a significant boost in power.

Key Features:

  • Big bore cylinder kit with an 85mm bore, increasing displacement to 304cc for enhanced performance.
  • Cylinder constructed from a high-silicon aluminum alloy featuring an oversized steel liner for durability and optimal heat transfer.
  • Steel liner is fused using a co-casting process, ensuring excellent heat transfer and combustion sealing.
  • CNC-machined forged piston designed for strength and precision.
  • Molybdenum disulfide piston coating reduces friction for smoother operation and increased longevity.
  • DLC-coated piston pin provides superior hardness and durability.
  • Includes high-quality piston rings and pin.
  • Complete gasket set provided for a seamless installation.
  • Features a laser-cut stainless steel MLS head gasket for reliable sealing.
  • Comes with a pre-calibrated GET Boost electronic module designed to work with this kit without requiring ECU or wiring modifications.
  • The GET Boost module connects directly to the injector and throttle body via a dedicated harness.
  • The GET Boost module is pre-mapped to optimize performance with the new cylinder configuration.
  • Piston is included in the kit.

Specifications:

  • Bore Diameter: 85.00 mm
  • Displacement: 304.00 cc
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