BSA don't make it easy for you, do they ? It's much easier to place a discrete switch on a WD16H as the brake arm is upwards and the operating rod passes close to the mudguard mounts. Furthermore, the (useless !) field stand hides a bit too.



I think you're going to have to put a small clamp around the rear tube pretty much where the footrest lug comes on the later bikes. The alternative might be to drill and tap the head of the stand bolt and fit a short screw to locate a tab holding the switch. There is next to no load applied if you're operating via a spring.

Here's the switch I use..Perhaps not suitable if you don't have panniers fitted...Those later bikes are so much more practical!...Ian

email (option): ian@wright52.plus.com

It may be easier and neater on an early M20 to fit the switch to the front brake rod ! :grinning:

It's a bit of a dilema on a machine that was never fitted with a brake light...to use a "period" switch as would have been used if they were fitted at the time or to use a smaller, more discrete unit, even though of a later design. I don't think there is a right or wrong answer. I don't like riding without a rear brake light though.

Thanks chaps
I might investigate mounting this switch onto a clamp on footrest set I have -
With no std lugs or as Ian highlighted - no pannier frames - the lug free frame keeps the switch very much inboard of the brake rod
Big storm here at weekend- so I’ll be in shed looking at this one
Bf
Jo’b

email (option): jonnyob1@googlemail.com