1934 Excelsior scout

[safe history man]

i am a good way on with a rebuild of an Excelsior scout 250 unfortunately the bike has no exsisting wiring and its not my strong point it is a simple system by the look of it head light,tail light,ammeter,dynamo (being rebuilt with modern regulator) Battery and horn .can any electric expert out there give me a quick sketch of a wiring diagram to help  sort it out
many thanks

[R]

This is going to largely depend on which headlamp switch and dip switch your bike has.
There are any number of wiring diagrams available out on the net, and in owners handbooks etc.
But its the connections on the back of YOUR switch that makes the difference.

Its not too difficult to add wires to get just the lights horn etc working from the battery, and initially omit the charging system.
That will need the correct connections to the headlamp switch - usually.

Is there no handbook or booklet for 30s Excelsiors with suitable wiring diagrams. ?
A Francis Barnett diagram or similar would suit.
I'll have a look in the Pearsons Villiers booklet, if no-one provides something more suitable in the meantime.
Cheers.

[R]

To start the wiring process off, this system is presumeably going to be -ve earth.
(positive earth being a 1950s invention.)

So a lead from the -ve on the battery goes to a suitable bolt on the frame close by.
Possibly with an inline fuse fitted in it.
A lead from the positive on the battery goes to the +ve on the ammeter.
The other side of the ammeter will have a power wire to the headlamp switch.
And from there to the dip switch and thence in parallel to the head bulb filaments
(assuming you have a dip beam.)
A lead off the switch will also go back to the tail lamp bulb.
And they may be a connection on the switch for parking lights....

Seperately, you also need a wire, directly from the battery, to the horn and thence the horn button.
Horns are always powered directly from the battery, without a connection to the ammeter (it can't handle the amps a horn pulls).  The horn is always 'live', and the horn button completes the path to earth..

The brake light also is connectly directly, so it always has power when you push the rear brake.
The brake light switch would likely have been optional back then, so you have to cobble something suitable.

Some folks prefer to fit fuses to different circuits - so the lights don't go out if the horn blows the fuse, etc.
This adds a level of complexity, and requires some consideration.
Its all easy when you do one step and one circuit at a time...
Hopethishelps !

[R]

Something else to watch, as an afterthought, is that not all Villiers etc bikes back then had battery lighting.
So some things like parking lights and tail lights were often odd voltages like 3v or 4v globes.
If they are then fitted to a 6v battery system, the globe life will be very short indeed.
Check carefully the voltages of these things - and even the headlamp globes.
Don't test them with 6v, use a lower voltage 1st, from small batteries...

[safe history man]

hi thanks very much for the info on the wiring it is fitted with a lucas switch marked with OFF,C,H ,L on the front of the switch and on the rear terminals
sh then a mounting pillar,T ,H,D+,L then another pillar see photo's don't know if this makes any sense

[R]

It does make sense, the C stands for charge in 1930s leccy systems.
Don't know a whole lot about how that works, think it switches in a wire wound resistance,
and just charges the battery (unregulated) with no lights switched on.
Ariels of the era used it, amongst others.
Unless you intend to do a lot of riding including lots of night riding, you probably don't need to have it enabled,
especially since you said you have a regulator.
Wartime bikes used it instead to light just the taillight, and the switch setting was changed to a T (for taillight).

Will have a look for a wiring diagram to suit, unless someone jumps in first.

[33d6]

In the 1930's Excelsior in their wisdom did not use the standard Villiers flywheel system for lighting. They used it for ignition only.  For lighting they fitted a separate Lucas dynamo in front of the crankcase driven from the engine sprocket. As this predates voltage regulators as we know them the original fitting was a standard 3 brush dynamo of the day with the rider controlling the rate of charge with the headlamp switch.

If you are going for originality and you have an original type Lucas dynamo fitted you need to look for a Lucas 3 brush dynamo wiring diagram. It is a standard wiring set up used on many bikes of the day. An obvious place to start is the VMCC Library.

As your bike has been around for 80 years it is more than likely someone has swapped components around and you may have a later 2 brush dynamo fitted which requires a voltage regulator. This requires a different wiring diagram and appropriate headlight switch.

I would suggest you start off by telling us what dynamo you have for the bike and we go from there.

Everything R has told you is correct for the Villiers system of the day but Excelsior didn't use it.

Cheers,   

 

[R]

Everything R has told you is correct for the Villiers system of the day but Excelsior didn't use it.

About everything I mentioned about the electrical system was applicable to any bikes electrical system - having noted the mentioned dynamo and regulator. 
But warned about possible Villiers bits getting into the act.

Ariel Sqaffers used about the same combination of components mentioned... ?

[safe history man]

hi 33d6 and R ,I have ordered a new solid state regulated and having the Dynamo (model E3D-3 LUCAS) fully refurbished and converted to a 2 brush also new battery and other bits like horn and ammeter the guy I bought the bike from has supplied the wiring harness but its a but of a mess.can anyone explain the legend on the main switch ,is it T for tail light ,H for headlight ,D for dynamo , L for lights and SH for ?   Excelsior seemed to be a law unto  themselves but in the 1930,s all they wanted was to try and make a profit from turning out the bikes to the masses , and the fact they stayed in business for so long using parts from all suppliers villiers,blackburn jap and lucas they must have been doing something right   thanks for your help guys

[R]

An Enfield wiring diagram of the era with similar switch (? tough to tell, they rarely show both sides ) has SH not connected - hence the lack of the screw in your slot ? - and their D  is an A, and goes to t'other terminal on the ammeter.
Can the supplier of your harness advise, they must have some info and a template to make up the harnesses.

Pretty much all british motorcycle makers used a vast range of suppliers - a list of components for most bikes reads like a whos who of british industry, quite apart from the engine and gearbox.
Dunlop, Avon, Amal, Smiths, Lycette, Doherty, Lucas, Millers, KLG etc etc, and thats just in the small parts.
Pretty much all the iron castings and alloy castings and metal pressings were also done by a small number of suppliers, tubing was by a small set of suppliers, paint/enamel from others, etc etc. Sometimes the warranty stated that branded parts were covered by a separate makers warranty - and it was joked that maybe only the decal/badge on the tank was covered by the makers warranty !  Very few makers made the whole lot, and suppliers come and go.
Have fun...