classic motorcycle forum

I'm set !
A Bantam ? tin bracket and later (?) Lucas lamp seem made for the job.
And that aforementioned small 6v battery.

Have a few bicycle ones. Decided there was no mileage in them = dry cell batteries again.
A better quality of rechargeables might work, but have proved elusive.
And look notably modern.

I'd still be curious what the model of this light switch is ??

they originally gave but wangling a replacement in and out of that headlight clip every month or so would drive me nuts.

You and everyone else, so after the one BSA supplied (if they ever did) went up the swanee doubtless they were never replaced. Just park off-road or where a copper isn't going to visit.
If someone was poor enough to be riding a little two-stroke in the 1950s, wasting money on dry-cells would have been well down the list of necessary expenditures.

I understand your lack of concern over lighting. Who does expect to go riding one of these beastliest at night anyway BUT, (there’s always a but) you do occasionally get caught out. Country town rides and rallies have caught me out a few times, somehow you end up at a local riders home or a different pub and bingo, it’s got dark quicker than you expected. I also like to have a brake/stop light fitted. I have little faith in the road users    following behind. Many only react to brake lights and never think beyond them.
You can fit a battery powered total loss system but then you’re always faffing around charging up batteries. Fit a basic direct lighting set up and you always have no hassle lighting but the brake light set up is iffy. There’s never an easy and simple 100% satisfactory solution is there.

I smiled at the 4.5v battery chatter. They can be sheer frustration. I don’t know exactly when they went off the market and I have mucked around making them up from two ‘D’ cells but eventually I got fed up and stopped bothering. I don’t know how many hours light they originally gave but wangling a replacement in and out of that headlight clip every month or so would drive me nuts.

Those little dry cell parking arrangements were no more than "work-arounds" for the odd parking regs in force in some parts of the UK. Some used to hang red and white parking lamps and even oil lamps on their car door handles at night.

I find this site the easiest of any to get on. No passwords needed. Click and go.

Still driving me nuts getting in. Won’t accept my ‘forever’ login and makes me sign in twice but at least I’m here.
Given that the electrics of the 9D changed over its production run and that a specified rear tail lamp bulb for those electrics wasn’t being made post war and no one knew if it would be again things got a little strange at times. The best advice I’ve found for all these circumstances is in Brownings coverage of the 9D in the early editions of his ‘The Villiers engine’ published by Persons, (definitely not Pitmans).
On top of that you need to consider whether you go for either of the Villiers standard options. Direct lighting that only runs when the engine runs or basic rectified lighting with battery but barely practical nowadays or best of all go for broke with modern electronics. Villiers copes with that surprisingly easy.
Do a little more research before you pile in.