S&S Cycle 3-5/8" Big Bore Cylinder and Piston Kit 91-9001 for Harley Engines

Enhance your Harley-Davidson engine with the S&S Cycle 3-5/8" Big Bore Cylinder and Piston Kit, part number 91-9001. Designed for building an 88-inch engine or replacing cylinders and pistons in existing engines with an S&S stock bore stroker kit, this kit offers reliable performance and durability. The kit includes three high-tensile cast iron cylinders with a 3-5/8" bore, forged pistons complete with rings and wrist pins, along with essential gaskets and fasteners. These components are engineered to provide optimal compression and power output, with a 7.5:1 compression ratio suitable for a range of riding conditions. The stainless steel head bolts with washers, base nuts, and base gaskets ensure secure assembly and long-lasting performance. It is compatible with engines featuring 4-1/4" flywheels, making it a versatile upgrade for many Harley models. Please note that crankcases must be bored to accommodate the larger cylinders, and the stock flywheel assembly should be rebalanced for optimal operation. Made in the USA, this kit is a reliable choice for motorcycle enthusiasts seeking to increase engine capacity and performance while maintaining quality and craftsmanship. Proper installation will require some engine modifications, including boring the crankcases and rebalancing the flywheel assembly, but the results are a significant boost in power and efficiency. Whether you're building a custom engine or restoring a vintage Harley, the S&S Cycle 3-5/8" Big Bore Kit provides the components needed for a high-performance upgrade that lasts.

Features:

• High-tensile cast iron cylinders with a 3-5/8" bore for increased engine capacity

• Forged pistons with rings and wrist pins for durability and reliable compression

• Includes head gaskets, stainless steel head bolts with washers, base nuts, and base gaskets for secure assembly

• Designed for 88" engines with a 7.5:1 compression ratio suitable for various riding conditions

• Compatible with engines using 4-1/4" flywheels; requires crankcase boring and flywheel rebalancing

• Made in the USA with high-quality craftsmanship for long-lasting performance