Athena P400485100038 53 mm Big Bore Race Cylinder Kit – Yamaha YZ85 2002-2018

Unleash the potential of your Yamaha YZ85 with the Athena P400485100038 53 mm Big Bore Race Cylinder Kit, designed for 2002-2018 models. This 2-stroke kit boosts displacement to 105 cc with a high-performance aluminum cylinder and piston, ideal for off-road racing. We price-match reputable online stores—contact us to ensure you get the best deal!

✅ What’s Included

• Athena Big Bore Race Cylinder (P400485100038)

• Aluminum cylinder head with removable bronze dome

• High-performance, hard-anodized power valves (non-OEM compatible)

• Forged race piston kit (piston, rings, clips, pin)

• Athena top-end gasket set with required seals and hardware

• Installation-ready design (crankcase modifications required)

• No additional hardware included beyond kit

🔑 Key Features

• Aluminum cylinder with nickel-carbide coating for durability and heat resistance

• Increases displacement to 105 cc with 53.00 mm bore

• Specially designed power valves for enhanced performance (replaces OEM valves)

• Forged race piston for superior strength and reduced weight

• Made in the U.S.A. with precision engineering

• 2-stroke engine compatibility

• Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

• Note: Crankcase modifications are required for installation.

📦 Fitment (Highlights)

• Yamaha:

  • 2002-2018 YZ85

• Notes: Always verify fitment by year, make, model, and engine specifications before ordering. Crankcase modifications are necessary; consult a professional mechanic or Athena instructions.

💲 Price & SKU

• Retail Price: $976.95

• SKU: 0931-0473 / P400485100038

• Note: We price-match reputable online stores—contact us for the best price!

• Weight: 4.33 lbs

• Dimensions: 6.33" (H) × 13.07" (L) × 8.26" (W)

• Availability: In stock. Ships next business day

🛡️ Warranty

• Contact Athena for warranty details (proof of purchase required)

🔧 Installation Tips

• Crankcase modifications required; seek professional assistance or follow Athena guidelines.

• Torque cylinder head bolts to Yamaha specs (~15-20 ft-lbs, consult manual).

• Adjust jetting (e.g., Mikuni carb) for increased displacement—start with richer mains (e.g., 32-35 pilot, 115-120 main).

• Verify power valve clearance and timing after installation.