Note the 1931 circular fork damper knob, Norton's own girders and Norton's combined rear break and sprocket unit. Not visible, but this is the first year a positive stop was used on the four speed Sturmey Archer box.
We're still looking for early-1931 CS1 Nortons; the earliest examples after Woods' prototype we have found thus far date from 17 June 1931 for the Works racers containing Norton's rear hub (below) and August 1931 for the CS1s still using Enfield rear hubs.
|Stanley Woods, 1931 Model CS1 Norton
finishing 3rd in the 1931 Senior TT
|Tim Hunt, 1931 Model CS1 Norton
finishing 1st in the 1931 Senior TT
|Tim Hunt, 1931 Model CJ Norton
finishing 1st in the 1931 Junior TT