🛠️ Grizzly 660 102mm Big Bore 686cc Top End Kit with Cylinder Head & Mudbuster Cam

Turn your Yamaha Grizzly or Rhino 660 into a torque monster with this complete 102mm big bore top end rebuild kit. Perfect for trail riders, mud boggers, or anyone looking for serious gains in power and reliability. This kit includes a brand-new aftermarket cylinder head assembly, oversized forged piston, Mudbuster camshaft, and upgraded valve train components — everything you need to refresh and upgrade your top end in one box.

✅ What’s Included:

• Aftermarket 102mm Big Bore Cylinder

• Forged 102mm Piston (Wiseco, JE, or CP)

• Piston Rings

• Wrist Pin & Circlips

• Mudbuster Performance Camshaft

• Heavy-Duty Timing Chain

• Cylinder Head Stud Kit

• NGK Spark Plug

• Complete Aftermarket Cylinder Head

• Rocker Arms (Intake & Exhaust)

• Rocker Arm Shafts

• Valve Adjustment Screws w/ Nuts

• Steel Intake & Exhaust Valves

• Inner & Outer Valve Springs

• Spring Retainers, Seats & Keepers

• Valve Guides & Stem Seals

• Top-End Gasket Kit

• O-Rings & Washers

📦 Fitment:

• Yamaha Grizzly 660 – All Years

• Yamaha Rhino 660 – All Years

🛡️ Warranty Info:

This kit includes a 30-day limited warranty against manufacturer defects. Engine must be installed and tuned by a qualified technician for warranty to be valid. Overheating, improper break-in, or installation-related failures are not covered.

🔑 Key Features:

• +102mm bore increases displacement to 686cc

• Includes new aftermarket cylinder head for full refresh

• Designed for high torque in low-end and midrange powerband

• Mudbuster cam delivers excellent throttle response

• All major top-end components included for a clean rebuild