- High quality inlet valves manufactured by G & S Valves - This valve is in a larger head size - 1.855". Probably the largest diameter head inlet valve fitted to SOHC Norton engines, this head would normally only be fitted to racing engines (I think I have one of these fitted in one of my racing methanol heads. Standard Model 30\40 stem diameter : 11/32" - Stem length: 4.650".
These valves already have the collet groove machined and are ready to fit. Note: Norton cammy valves were made in a variety of lengths over the years. This length - 4.650" is also relatively common (and I believe more so with the larger valve size). If you have an original then measure that. If you are unsure please email me.