Earlier design approaches to C-D magnetos for chain saws have been to make them directly interchangeable with their conventional counterparts. This, however, failed to make full use of the advantages offered by Breakerless C-D Ignition toward optimum chain saw design. The approach described in this paper resulted in a simple four-piece system which is easy to install and service. Its simplicity greatly adds to its reliability. The improvements in this system lie in the use of a modular assembly with all of the ignition components removed from underneath the flywheel, a new approach to prevent the reverse running of the engine, and a specially designed step-up transformer matched to this C-D system.