S&S CYCLE Cam - 551 Series - Chain Drive - Twin Cam 106-4858

If you're running a Twin Cam 106 and want measurable gains in low-to-midrange torque without a complete top-end rebuild, the S&S Cycle 551 Series gear drive cam delivers. By eliminating timing chain lash and reversing rear cam rotation, this kit achieves tighter valve timing accuracy and opens clearance for higher lift profiles—all while compatible with your stock pushrods and springs. You'll feel the difference strongest between 1,000-4,000 rpm, exactly where touring bikes need responsive power.

Key Specifications:

• Gear drive design—elimates chain lash
• Designed for Twin Cam 106 engines
• 9:1 to 9.9:1 compression ratio range
• Peak power: 1,000–4,000 rpm
• Bolt-in installation (touring applications)
• Compatible with stock pushrods, springs, lifters
• Includes inner and outer gears
• Includes inner and outer bearings
• Includes gaskets and instructions
• Requires professional installation tools
• Requires gear cover material removal
• Requires new cam bearings and gaskets
• Requires clearance verification (coil bind, valve-to-valve, valve-to-piston)
• Slightly increased valve train noise
• Made in the U.S.A.
• MPN: 106-4858