Hi
Having just about completed my 1947 BSA B31 the final item was a speedo which eventually I found (at a cost) but due to increasing health issues I am selling the bike, but first I need to attach the speedo, and I have suddenly discovered there is no illuminating bulb or holder, and I can't seem find one for sale, the hole for it is about 5/8" and the speedo model is S433/1/L can anyone point me to one please.
The bulb holder for my 1950 B33 was missing when I bought it. I got one from the green spark plug company. The speedo has a different code number to yours but it could well be the same fitting. I also managed to find a soft white led to fit it which uses virtually zero electricity.
I saw those but couldn't see the size, maybe I will buy one and see, Thanks Greenfield.
This is a standard chronometric bulb holder assembly, it is (assuming your instrument hasn't been altered) exactly what you need. Available almost everywhere you look.
Paul.