Brake light

[rtw]

Anyone got any idea how or what switch would have been on the Excelsior 1950 model! I am clueless to where it would have been mou ted and what it may  have looked like?

[R]

Since this is before rear brake lights were required by law (?), this is a somewhat murky subject.
And some Villiers powered beasties had near minimal electrics, so brake lights required quite some cobbling (by owners) to actually give them such luxuries.

What make of electrics does your bike have - Miller ?
And does it have a battery ?
What does the parts list for your bike show - anything ?
The period wiring diagrams sometimes show dotted lines for the brake switch wiring.
And the rear lamp may need some upgrading to have a brake light function.

This is the style of switch you sometime see on this era of bikes (this one a replica)

It usually sits on a little metal plate, and anchored by any conveniently located bolt nearby.
The spring attaches to the brake rod, usually by a little clamp
Other brake light switches are available, quite a variety in fact, its just a matter of obtaining something and figuring out where to attach it so it reliably lights up and retracts.
I'll find a pic of one on a bike, although it may not suit your setup.

Rear lamps for bicycles, with LED technology possibly can be adapted  - they use battery power, which can be conveniently switched on/off for more limited road use. And require no vehicle electrics, just a suitable switch.
Hopethishelps.

[R]

Maybe this pic will be helpful.
Note there is a strap around the back of the frame tube, straight onto the switch.
(and I don't know why so little paint is in evidence !)

http://matchlessclueless.com/wp-content/uploads/2010/12/R0033094-small.jpg

[33d6]

R is quite correct and very helpful. Villiers only provided two lighting circuits for their 1950 offerings regardless of what make of bike their engine was fitted to. First was a very simple lighting circuit connected directly to the lighting coils where the amount of light given out rose and fell with the engine revs. No battery present, no brake light shown on the circuit diagram and little chance of fitting anything effective. This is the lighting circuit many prefer as it's so simple but basically not worth a cracker.
The second circuit included an early crude half wave rectifier and battery which provided a steady light that does not rise and fall with engine revs. On this circuit diagram Villiers included a dotted line from the battery to the tail light showing how a brake light could be fitted if the owner so desired. As it runs directly from the battery it operates regardless, independent of lights on or off. Villiers did not provide either a brake light switch nor a stop/tail light. That was entirely up to either the maker of the bike or the owner so anything period is okay.
Given the monumental advances in electronics since then it is very easy to improve on the original with little effort. That doesn't mean you get brilliant lights. The originals are dismal, with improvements they will be about average. Don't ask me how I know.

Cheers,

[vintage_keith]

Just a comment on R's mention of the use of cycle rear LED lights..........I went down this route a couple of months back, as I wanted a rear brake light for a veteran (no electrics).
I went down to the local cycle accessory outlet, chose one with quite a large illuminated area and came home ready to work wonders.
I fitted a universal brake light switch low down, clamped the spring onto the dummy belt rim brake rod, and wired back to the picnic hamper I have on the rear carrier. I took the batteries out of the new light, and soldered wires to each internal terminal, drilled a hole in the body, brought the wires out and then sealed up the body. I then placed a remote battery pack with on/off switch in the picnic hamper and connected all up. The LED light has 3 modes, so chose the permanent illumination mode and left LED switch in this position. Adjusted until brake switch brought light on, and off as anticipated.
Imagine my surprise when I went out for a run and it stopped working - it turns out the LED circuitry has something that prevents this type of use! Anything more than 2 1/2 minutes gap between presses of the brake pedal, and it stops working! Dismount from the bike, press the LED switch 3 or 4 times to get back to square 1, and it becomes functional again.
I contacted the importers AND the Japanese manufacturers, both were totally unhelpful.

At that point I gave up!

[R]

Interesting observations.
My thoughts were to measure the voltage that is applied to the leds, and apply this directly to them - bypassing the controller. Haven't actually installed it yet...

Maybe there is a market for a suitable self-contained unit/kit for motorcycles ?
Disguise it as a (jumbo) acetylene rear lamp ??
Or picnic basket accessory ...

[rtw]

Hi, been busy and only just got back to read replies. thank you.

i can only assume the tail light is original, it has two wires coming out the back  and two contact points for a twin element globe. I don't believe the bike ever had a rectifier and was only ever direct wired from the magneto. An Interesting thing is on the brake shaft that crosses through the frame to the brake rod there is a lever cast into it with a hole at the top that I suspect some how possibly connected to a switch. I will post a pic later today.

[rtw]

finally took a picture, as you can see the hole just below where the brake rod couples there is hole on a tag, it must have been designed for something.
I had it running last night, took it for a spin around the block. it wouldn't keep up with my BMW! but it goes ok. 

[33d6]

Excelsior made two versions of the Roadmaster in 1950, the R1 rigid and your R2 deluxe with rear plunger suspension. The R2 had a battery and rectifier and should have the second of the wiring circuits we discussed earlier. This allows for the stop light addition. The ancient selenium rectifier in those days was a monster being roughly the same size and thickness as a slice of toast bread, ie, bread sliced thicker to make toast. On my 1951 James de luxe with exactly the same engine and wiring set up the rectifier was bolted flat on the back of the toolbox. Yes, that's right. It was in the path of every bit of road muck going---but it worked. Have a look on the back of your toolbox. You may find evidence of the rectifier being mounted there. Otherwise they were usually mounted under the seat. I'll have a look around my stuff to see what I can find but meanwhile I can only suggest you start planning for a complete rewire which will improve things a lot.

Finally (and I'm being extremely cheeky here) please remove those fork gaiters. Excelsior never fitted them and they really don't help the looks do they. It's like a pretty girl in party dress wearing wellingtons.
 
Cheers,

[33d6]

Having a closer look I can see yours is the 122cc Universal, not the 197cc Roadmaster. Not to worry, except for the engine capacity they are otherwise identical and same remarks apply.

[iansoady]

That's very pretty - well done.