- Coil Valve Spring Top Cup to fit early SOHC (coil spring variant) Model 30/40 International, CS1/CJ as well as pre-1948 Norton OHV models.
These valve spring parts (see also Item 0672 for the corresponding coil valve spring bottom cup that match with this item) are CNC manufactured by us, dimensions copied from original patterns. They are steel as per originals, then they are chemically blackened to protect from rust. They are also stored in light Duck oil.
Coil springs were used on all early Norton SOHC Carrol engines - Model 30/40 and CS1/CJ until 1935. Works engines first used hairpin valve springs in 1934 and Model 30/40 International engines switched to hairpin valve spings in 1935, but CS1/CJ engines continued with these coil springs . They were also fitted to OHV engines (Model 18,50,55, 19, ES2) all the way through the 1940's and through the different later design of 1950's OHV engines until the late 1950's. This top cup plate is of the correct type for OHV engines fitted up to 1948 - identifiable from later 48 onward OHVmodels because the earlier engine had rocker box with seperate alloy distance pieces between head and rocker box.
Note: If you have a post 1948 OHV model (identifiable by pushrod tubes slightly further apart than pre-48 models and a single part see item 0674 for corresponding top cup for later 1948 onwards OHV valve engines, not this version
The corresponding valve springs for these cup plates are Item 0677. Note however, collets for SOHC and OHV engines are different, of which we sell all the different types
The engine photographs in this listing show the early coil spring SOHC engine - if fitting these to an SOHC engine you need to check it is the correct coil spring cylinder head - not a later Inter hairpin head (normally identifiable because hairpin heads have the seat where the spring holder sits milled flat). To help with this identification - I have attached a picture from the 1937 Norton Spare Parts catalog which shows a hairpin International cylinder head (8771) next to a coil spring CS1 cylinder head (8772) so you can see the detail differences
This listing also shows two pictures of the 1938-48 style OHV engine this top cup also fits - but they also fit pre 38 OHV engines