| Diagram | Fig. 17 — NACELLE, HEADLAMP AND SWITCHES · ref 28 |
| Subsystem | electrical |
| Listed in parts books | 1960–1962 |
SWITCH, SA41 BSA PU
Lucas-type 41SA light switch, part number 31784, used across various British bike electrics.
This is a Lucas-type 41SA switch, part number 31784, listed in catalog records as the light switch used across a range of British bikes including BSA and Norton applications as well as Triumph. Catalog listings tie it to the SA41 designation, which was a common headlamp/light switch used in this era of British electrics.
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The canonical description on our end is terse - just the switch designation and a note about BSA fitment in a pre-unit context - so we're relying on the broader catalog record to confirm what this part is. If you're chasing this off a parts book number, this is the one, but confirm the switch body and mounting match what's on your bike before you order.
Electrical switches like this typically control headlamp and/or pilot light circuits, but we don't have enough part-specific detail on file to say exactly which functions this one handles or how many positions it has. Give us a call if you want to talk through the wiring before buying.
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