S&S Cycle 33-5073 520 Series Camshaft for Evolution Big Twin Engines

The S&S Cycle 520 Camshaft (33-5073) is a short-duration, emissions-compliant cam grind engineered specifically for Evolution Big Twin engines. Designed as a direct replacement for S&S emissions-certified powerplants, this cam features minimal valve overlap to reduce unburned hydrocarbon emissions while still delivering strong low- to mid-range torque in the 1,000–4,500 RPM power band.

Every S&S cam grind undergoes extensive dyno, street, and track validation before release, ensuring proven, real-world performance. The 520 is compatible with stock or ported heads and works with engines up to 96 cubic inches and compression ratios up to 10:1, making it an ideal choice for touring applications, two-up riding, and dresser-style motorcycles. It is also commonly supplied with many emission-compliant engines used by aftermarket motorcycle manufacturers. Sold individually.

Camshaft Specifications:

• Grind: 520 Series
• Valve Lift (Intake): 0.520 in.
• Valve Lift (Exhaust): 0.520 in.
• Intake Duration: 220°
• Exhaust Duration: 232°
• Intake Open / Close: 0° BTDC / 40° ABDC
• Exhaust Open / Close: 50° BBDC / 2° ATDC
• Intake Lift at TDC: 0.086 in.
• Exhaust Lift at TDC: 0.094 in.
• Lobe Separation: 112°
• Tappet Type: Hydraulic
• Power Range: 1,000–4,500 RPM

Installation Requirements:

• High-lift valve springs required
• Installer must verify coil bind, valve-to-valve clearance, valve-to-piston clearance, and cam lobe-to-case clearance

Additional Part Numbers: DS199224 | 498565

⚠ Emissions Notice: Not legal for sale or use in California on any pollution-controlled motor vehicle. Not legal for sale or use nationwide on any federally pollution-controlled motor vehicle under the Clean Air Act.