To preserve an important piece of Brooklands’ history Jim Baxter has built up an interpretation of the motorcycle ridden by G E (`Wizard) Stanley there in 1912; he was the first to exceed 75mph on a 500cc machine and set the class hour record to over 67mph.
The single-cylinder engine had side valves, and was said to have pioneered overlap timing, the exhaust cam which prodded its valve via a right-angled roller-ended rocker also opening the inlet valve at one point after the inlet cam and similar rocker had ceased to do so. The Singer engine also has its liberally drilled cutaway piston, with centre strut to the crown, above the gudgeon-pin. The engine has been put into a single-gear belt-drive Quadrant in stripped racing trim (below), and is transported in Baxter’s open Lancia Lambda.
This has set me wondering when valve overlap was first used? If not on this Singer racing engine, when? Griffith Borgeson, in his erudite book The Classic Twin-Gun Engine (of which my copy has 42 typed corrections by the conscientious author) admitted to not knowing, but thought it might have been used first for the Henry-Peugeot racing engines of 1913/14. Or was it much earlier?