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Big Bore Kit with Camshaft - 285cc

XR250R '96 - '04
WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

285cc big bore kit includes:

Wiseco piston 78.00/+5.00 10.5:1 (with rings, pin & clips): 

  • All Wiseco Pistons are forged from high silicon, low expansion aluminum which offers superior strength, reduced weight, improved heat transfer, and longer life.
  • Diamond turned finish from one of the many CNC computer controlled turning centers guarantees you a perfect finish with no size variation. Wiseco pistons can be installed in any of today’s cylinder bore compositions
  • Wiseco’s state-of-the-art computerized manufacturing facility is dedicated to supplying both the high-perfomance racer and recreational enthusiast with the finest forged piston available in today’s market place.

HotCams stage 1 camshaft:

  • High-performance racing camshafts
  • Stage 1 performance camshafts are drop-in cams that are designed to be used with stock valve springs
  • In most applications, Stage 1 cams deliver more torque.

Complete top end gasket set:

  • High-tech materials provide unmatched reliability and performance
  • Rebuild the engine with total confidence as each set is designed for durability and accurate fit
  • Oil seals are genuine OEM replacement seals
  • Performance sets designed for a piston replacement
  • Includes every gasket, O-ring and seal required to rebuild a top end; valve seals, head, base, exhaust, tensioner, and other misc. gaskets and O-rings
  • Does not include formed rubber valve cover gasket
  • High-compression kits use .012" thick base gaskets to raise compression
  • Cost-effective way to raise compression without expensive high-compression pistons or cylinder head work
  • All gaskets made in the U.S.A. 

This is a great combination and a big 'bang for the buck' performance increase. 

No re-sleeving required. You will have to have your cylinder bored to fit the larger piston.

CARB race use only
Ships in 3-5 business days