1929 Excelsior (UK)

[PaulBurton]

BTH offered light sets for only a few years of the late twenties.  I have a bike fitted with a BTH "dyno-mag", and some years ago managed to acquire at great expense a correct headlight to match it.  That's the only BTH headlight I have ever seen!!  To describe them as uncommon is a sweeping understatement.   The BTH tail light is a generic bullet styled thing, and so I've given up on finding one.  Any sort of late twenties electrical kit is hard to find, and expensive if you do; I'd be using the Miller headlight on the basis that you have it.

Somewhere I think I have a BTH brochure and wiring diagram.  I'll see if I can find it and scan a copy to post.

cheers,
JFerg

Thanks! That's really useful info. I'll treasure the Miller! If you do find the BTH brochure that would be a great help.
Tks again
Paul.

[33d6]

If you want more info on the BTH mag/generator set up the VMCC Library lists a 1930 BTH Instruction Book for it. You may as well see what BTH themselves had to say about their product.
It's a lovely and oh so complete bike you have there and a really good one. It was also available with a 250cc JAP engine. Excelsior won the 1929 Lightweight TT with one of these. It's about as good as you can get for it's time. Lucky man! 
Cheers, 

[JFerg]

Paul,  Attached some extracts that show precisely what the BTH light set consisted of.  Quality isn't flash, but they're scans of copies.  You can see that the wiring is far from complex!

At present you have a BTH magneto-generator, a Miller head light and a Lucas tail light.  All of it is of the same period, more or less, but more importantly, it's all been on the bike for a long time, and you have it.  Therefore I'd be using it all and paying no heed to any "originality" sniffles.

cheers,
JFerg

[PaulBurton]

If you want more info on the BTH mag/generator set up the VMCC Library lists a 1930 BTH Instruction Book for it. You may as well see what BTH themselves had to say about their product.
It's a lovely and oh so complete bike you have there and a really good one. It was also available with a 250cc JAP engine. Excelsior won the 1929 Lightweight TT with one of these. It's about as good as you can get for it's time. Lucky man! 
Cheers,

Thanks - that's a useful lead to follow through. Yes, the old gal is pretty well 'all there' which is a good start. What's a bit special for us is its history - in our family from 1931. Not quite a single owner but not far off! Thanks again for your help and comments.
Paul.

[PaulBurton]

Paul,  Attached some extracts that show precisely what the BTH light set consisted of.  Quality isn't flash, but they're scans of copies.  You can see that the wiring is far from complex!

At present you have a BTH magneto-generator, a Miller head light and a Lucas tail light.  All of it is of the same period, more or less, but more importantly, it's all been on the bike for a long time, and you have it.  Therefore I'd be using it all and paying no heed to any "originality" sniffles.

cheers,
JFerg

Thanks so much for this - a real help! I think even I can manage that wiring!! Yes, I intend keeping it all as much 'as is' (but restored!) as possible.
Thanks again for your help!
Paul.

[mini-me]

For a freebie with family history that looks a great find,  I wouldn't mind it myself.

as has been said, keep it as it is equipment wise.
so many these days are obsessed with matching this and matching  and don't bother to research or understand history.

Back then the owner would chop and change accessories and equipment as he felt like it, same as customisers do today.

The period catalogues are a guide, not holy writ, or infallible.

[PaulBurton]

For a freebie with family history that looks a great find,  I wouldn't mind it myself.

as has been said, keep it as it is equipment wise.
so many these days are obsessed with matching this and matching  and don't bother to research or understand history.

Back then the owner would chop and change accessories and equipment as he felt like it, same as customisers do today.

The period catalogues are a guide, not holy writ, or infallible.

Thanks for good and helpful advice - I'm a novice in this game!!

[33d6]

Hi Paul,
I've been closely looking at your photos. Excelsior also made that model in 1930. Identical, except in 1930 they introduced chrome plating on the tank and a different transfer. You have the 1930 style tank.
This fits quite well with a 1929 made JAP engine as the bike year starts in September or so. It's not the calendar year. All early production 1930 Excelsior would carry a 1929 JAP engine number.
I think your bike may be a 1930 model.
I got my copies of the 1929 and the 1930 catalogues from BMS. If you get your own copies you'd see the same.
It makes absolutely no difference to what you have to do or whether it's vintage or not or anything else but you might find authorities get funny about paperwork when it comes time to put it on the road.
Cheers,

[PaulBurton]

Hi Paul,
I've been closely looking at your photos. Excelsior also made that model in 1930. Identical, except in 1930 they introduced chrome plating on the tank and a different transfer. You have the 1930 style tank.
This fits quite well with a 1929 made JAP engine as the bike year starts in September or so. It's not the calendar year. All early production 1930 Excelsior would carry a 1929 JAP engine number.
I think your bike may be a 1930 model.
I got my copies of the 1929 and the 1930 catalogues from BMS. If you get your own copies you'd see the same.
It makes absolutely no difference to what you have to do or whether it's vintage or not or anything else but you might find authorities get funny about paperwork when it comes time to put it on the road.
Cheers,

Thanks for this! The tank is (or rather was once!) chrome plated. I have had to get a new one made - exact replica, as the metal was too thin and perforated.
We have no documents for the bike (except the second hand sale receipt from 1931) so I only had the engine number to go on.
Incidentally, where is the frame number normally stamped? I have hunted high and low and cannot spot it!
Thanks again for the clarification.
Paul.

[33d6]

No frame number? Why am I not surprised? Yours is the fourth Excelsior of the period I've come across without a frame number. I don't know what Excelsior were up to but something went weird in the late 1920's after which they started a new frame numbering sequence in 1931. The frame numbers started A for 1931, B for 1932 and so on. After the year letter came the model number and then the actual frame number. At one glance you can identify what year and what model. All well and good for the '30's but no good for the immediate period beforehand.

I used to have all sorts of wonderful theories why late vintage Excelsior frames in Australia weren't numbered but yours is a home market model so all my theories are out the window.
So, sorry Paul, can't help.

Cheers,

[PaulBurton]

No frame number? Why am I not surprised? Yours is the fourth Excelsior of the period I've come across without a frame number. I don't know what Excelsior were up to but something went weird in the late 1920's after which they started a new frame numbering sequence in 1931. The frame numbers started A for 1931, B for 1932 and so on. After the year letter came the model number and then the actual frame number. At one glance you can identify what year and what model. All well and good for the '30's but no good for the immediate period beforehand.

I used to have all sorts of wonderful theories why late vintage Excelsior frames in Australia weren't numbered but yours is a home market model so all my theories are out the window.
So, sorry Paul, can't help.

Cheers,

Well, that's reassuring in one way but distinctly puzzling in another way. I will at some point try to track down the original registration details - if I succeed it will be interesting to see what, if anything, is given as frame number!
I'll keep you posted on progress - but for now, thanks again for all your help and comments thus far!
Paul.

[mini-me]

OF is a Birmingham reg issued only from May 1929  to April 1930.

so that narrows it down and maybe Birmingham is the place to start asking?

[PaulBurton]

OF is a Birmingham reg issued only from May 1929  to April 1930.

so that narrows it down and maybe Birmingham is the place to start asking?

Thanks - that's a good lead. I knew it was Birmingham or nearby but had no fix on the dates!
Paul.

[PaulBurton]

Hi friends out there! I've been quiet on this for a year but work is progressing well on restoring the bike. I'll try to post a couple of update pics in the next few days. Meanwhile, concerning the registration date, I contacted the Kithead Trust who told me all Birmingham records have been destroyed. They did indicate that this bike with reg OF2038 would probably be from late summer of 1929 as OF6368 was the first number issued in 1930.

On another matter it looks like I am going to have to dismantle the clutch as it won't disengage. It's a 3 plate with central push rod and has 4 spring screws. Anyone got any hints before I take the plunge?

[chris mac]

The BTH mag dyno shown was in use by a number of manufacturers until the mid 30s. It puts out a snarling 4 amps for 24 watts, regulation is by a four position switch mounted in the headlamp. A BTH cut out was fitted in a separate housing usually mounted on the top of the tool box or on the frame. As pointed out in another post, pretty much any wiring diagram for a 3 brush dynamo will get you close, I doubt your Miller headlamp is original, but if it has the 4 position switch can be made to work. Original headlamp usually supplied with the BTH unit was the Powell and Hamner, I believe they merged in about 1926