Sunbeam introduced overhead-valve engines in the mid-1920s having established its not inconsiderable sporting credentials with sidevalve machines. Introduced in the autumn of 1930, the all-new Model 10 featured an overhead-valve twin-port engine incorporating an in-sump oil reservoir, while its conventional cycle parts were lighter than hitherto. Although something of a departure from traditional practice, for the first time there was no fully enclosed chaincase on a Sunbeam roadster, the Model 10 was a capable performer of exceptional frugality, over 100mph being achievable. The Model 10 was produced for only two years before Sunbeam reverted to the old Model 8.