This is the gearbox kickstarter spring fitted to the 4 Speed Sturmey Archer models from approximately 1932-34, visually similar to the Norton gearbox spring that followed it, this spring has a wider diameter. It is identifiable from earler Sturmey gearboxs in having one tang facing inwards, and the other facing backwards .
Price is each.
We used a genuine 'New Old Stock' Sturmey Archer (for Norton models) kickstart spring for the pattern for manufacturing these springs - so they are as per originals.
It is difficult to be definitive about exactly which models (and when) were fitted with this type of kickstart spring - but reading through Norton literature of the period - this spring seems to have been fitted mainly to the Four Speed (CSR) Sturmey Archer gearbox types. The 4 speed gearbox looks to have be first supplied on SOHC (Mod 30 and 40) models on their introduction in 1932. In 1933 the 4 speed was also offered for the SOHC CS!/CSJ. Then for 1934 it was shown as available for all models - albeit with a slightly different positive stop mechanism on OHV/SV models.
In late 1934 - early 1935 the Sturmey Archer gearbox was replaced with Norton's own similar design, based on the earlier Sturmey design but with many smaller design differences - including the kickstarter spring, which was easily identifiable by having a smaller diameter coil section.
For identification if you are not sure if this is the correct spring for your gearbox - It has an outer diameter of 47.5mm and a depth of coils of approximately 21mm
This is now an extremely difficult spring to find, and many original gearbox's are likely to be suffering with the original spring worn and tired - this new spring should help revitalise the kickstart lever returning!