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We will be leaving the office slightly earlier than usual this Friday 5/24 at 2pm (Pacific Time) and will be back in action on Tuesday 5/28 at 9:30am. We are taking a little break to enjoy some quality time with our families and to celebrate the Memorial Day weekend.

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Big Bore Kit - 290cc, Athena

CARB   WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.
WR250R '08 - '18 WR250X '08 - '11
  • Kit includes aluminum cylinder with nickel-carbide coating designed with larger water jackets
  • Specially designed, high performance, hard anodized power valves (cannot use OEM)
  • Forged piston with molybdenum coating
  • Does not include cylinder head.

You will need to tune your EFI with something like the Power Commander V to get the most out of your Big Bore kit.

Add EFI Programmer, Dynojet Power Commander 6
Ships in 3-5 business days
$999.95