Description
If you’re running a touring bike and want measurable power gains without a complete engine rebuild, the S&S Cycle 551 Series Gear Drive delivers. By eliminating timing chain lash and reversing the rear cam’s rotation, this kit unlocks higher valve lifts and stronger low-to-midrange torque across the entire powerband. The precision of gear drive timing means you get consistent, repeatable performance—no more chain stretch robbing you of reliability or power.
This is a professional-level installation requiring machine work, specialized tools, and verification of critical clearances. But if you’re committed to extracting real performance from your engine, the results justify the effort.
- Material: 4130 chromoly construction
- Fitment: Touring bikes only
- Compression ratio: 9:1–9:9
- Peak power band: 1,000–4,000 rpm
- Installation type: Requires professional fabrication
- Timing accuracy: Eliminates chain lash
- Valve lift: Increased capability
- Compatible with: Stock pushrods, springs, lifters
- Included: Cams, inner/outer gears, bearings, gaskets, instructions
- Material removal: Required from gear cover
- Tools required: Hydraulic press, professional-level equipment
- Pre-installation checks: Coil bind, valve clearances, piston clearance
- Maintenance note: Replace cam bearings and gaskets
- Characteristic: Increased valve train noise (normal)
- Origin: Made in the U.S.A.
- MPN: 330-0100
