S&S CYCLE Super Stock® Engine Case for Big Twin '48-'64 – Part Number 31-0008

The S&S CYCLE Super Stock® Engine Case (Part Number 31-0008) is a high-quality component designed specifically for vintage Big Twin motorcycles from 1948 to 1964. Crafted with precision, this engine case features line-honed bearing races and a machined breather cavity to optimize breather timing and maximize oil scavenging efficiency. It is engineered to support 3.4375-inch cylinders and is tapped with 1/4-inch-20 threads for gear covers, oil pump, tappet guides, timer, and timer advance components, ensuring seamless integration with your motorcycle's existing system.

This engine case includes essential hardware such as crankcase bolts, washers, nuts, cylinder mounting studs, a magnetic drain plug, assorted breather and oil line fittings, a top-end oil screen spring and plug, and a sprocket shaft Timken® bearing assembly. The oil seal, pinion shaft main bearing race, cam needle bearing assembly, and oil pump shaft bushings are all included, along with detailed installation instructions. Designed for durability and precision, it is machined for '48-'62 panhead cylinder oil feed and '55-'64 tin primary configurations. The case is drilled for 5/16-inch generator mounting bolts and is compatible with Timken-style sprocket shaft bearings and '58 and later pinion bearings, ensuring reliable performance.

Manufactured in the USA, this engine case is suitable for use with models that feature outside oil lines, requiring the use of the oil port at the rear of the tappet block or in the gear cover, along with custom oil lines. The generator crankcase gear kit, which includes the circuit breaker drive gear, idler gear, and circuit breaker gear, can be purchased separately to complete your assembly. This robust engine case is an excellent upgrade or replacement part for restoring or building vintage Big Twins, combining quality craftsmanship with precise engineering for optimal performance.

Features:

• Line-honed bearing races for smooth operation and longevity

• Precision-machined breather cavity to optimize breather timing

• Supports 3.4375-inch cylinders with tapped 1/4-inch-20 threads

• Includes crankcase bolts, washers, nuts, and mounting studs

• Machined for '48-'62 panhead cylinder oil feed and '55-'64 tin primary

• Compatible with Timken-style sprocket shaft bearings and '58+ pinion bearings

• Drilled for 5/16-inch generator mounting bolts

• Made in the USA with high-quality craftsmanship

• Designed for models with outside oil lines, with specific oil port requirements

• Includes essential components like oil seals, bearing races, and oil line fittings