As did the majority of their contemporaries, Norton relied on the sidevalve engine until the introduction of its first overhead-valve design in 1922, the Model 18. This proved a very successful road machine.
Competition was a rather different story, as Velocette's OHC KTT had dominated the field in the 1926 Junior TT. Norton responded with a similar overhead camshaft engine the following year.
The Walter Moore engine proved an excellent design; it retained the Model 18's 79x100mm bore and stroke and employed bevel gears and a vertical shaft to drive the cams in similar fashion to the Velocette. The new machine sported a cradle frame and, for the first time, a saddle tank. At its first outing it secured a win in the 1927 Isle of Man Senior TT with Alec Bennett at the helm, finishing a full 8 minutes in front of the second place machine. Stanley Woods, also on a CS1, established a new lap record of 70.99 mph.
The production version of the new CS1 duly appeared at the Motor Cycle Show later that same year and continued as Norton's top-of-the-range sports machine until the introduction of the International.
This landmark sports model is regarded as one of the desirable Norton motorcycles by collectors.
Production Years: 1927-1939
Power: 18.3 KW
Displacement: 490 cc
Type of engine: OHC Single
Maximum speed: 85mph (1928), 190 km/h (late models)
Weight: 145 Kg
Sources: Motos Antigua HD, et al
If you have a query or information about Norton motorcycles please contact us