Norton 1929 “Model 18” 490 cc OHV single frame # S 36388 engine # 50866
Like the majority of their contemporaries, Norton relied on the side valve engine until the 1920s, when the existing and well-tried 490cc unit was used as the basis for the firm’s first overhead-valve design.
Penned by James Lansdowne Norton himself and first seen in prototype form in 1922, the overhead-valve Norton made little impact in that year’s Senior TT, though at Brooklands D R O’Donovan raised the world 500cc kilometre record to over 89mph using the new motor.
For 1923 the 79x100mm bore x stroke OHV model was catalogued as the Model 18.
At its introduction it got the factory code word of “Speedy”, which certainly showed some foresight: speeds up to 100mph were attainable with carefully tuned engines.
In the course of 1923 a number of speed events were won, but in 1924 the Model 18 really showed what it was capable of.
In June Alec Bennett won the senior TT on a model 18 with an average speed of 61.64 mph; the sidecar TT was won by George Tucker on a 588cc version of the model.
Both the French and Belgian GPs were won, and Bert Denley captured the coveted British One Hour Record at 87.07mph.
In 1925 a new drum brake and Webb centre spring forks were featured; in 1926 a mechanical oil pump on the magneto drive cover was added.
The 1929 Model 18 got a saddle tank – this had already been fitted in 1928 to several other Norton models – and the catalogue promises us the following other improvements in appearance and layout: “The separate oil tank has been entirely remodelled and now has an enhanced contour following the radius of the rear mudguard and fitting close up to it.
The primary chain is suitably housed in a guard of cast aluminium; the rear brake pedal has been positioned more accessibly; the saddle is mounted directly to the frame in those models in which the magneto is housed in front of the engine; the magneto is totally enclosed in a cast aluminium dust and waterproof cover on a platform rigid with the engine.
Thus the 1929 Norton is a better Norton than ever, a motor cycle of superlative value in every respect.”
This potent ohv sportsman’s mount is an older restoration that comes with full electric lighting.