The Athena Big Bore Cylinder Kit with GET Boost increases the displacement of compatible 250 cc motocross engines to 282 cc. It combines a larger cylinder and piston with a pre-calibrated electronic module designed to manage the Big Bore configuration. The kit is intended to provide greater power and torque across the rev range while maintaining smooth, controllable delivery.

Features

• GET Boost is pre-calibrated for the Big Bore configuration to manage engine operation and power delivery.
• The module connects to the original system through a dedicated harness without permanent changes to the stock ECU or motorcycle wiring.
• The cylinder is engineered for the increased mechanical loads and thermal demands of motocross use.
• The piston is designed to withstand the loads associated with the increased displacement while maintaining low weight and dimensional precision.
• The gaskets provide sealing for the new cylinder assembly.

Specifications

• Cylinder bore: 86 mm.
• Engine displacement with kit installed: 282 cc.

Kit Contents

• Big Bore cylinder.
• Forged piston, wrist pin and piston rings.
• Complete gasket set for cylinder installation.
• Pre-calibrated GET Boost electronic module.

Cross-Reference OEM Part Numbers

• Athena: P400270100027.

Vehicle Fitments

• GAS GAS MC F 250 cc: 2024–2027.
• HUSQVARNA FC 250 cc: 2023–2027.
• KTM SX-F 250 cc: 2023–2027.