Crane Cams HI-4N Ignition Module for Harley Davidson 1970-99 Big Twin; 1971-200 Manufacturer Part No: 8-6100 1-piece machined aluminum housing reduces vibration and improves heat dissipation and reliability Improved kickstart algorithm designed to start as easily as points BCD switches with solid detent and legible marking allow easy and repeatable adjustments of mode, advance rate and rev limit Single-fire and dual-fire function built into a single module