classic motorcycle forum

Make an interesting and very pretty old banger !
Suggest you contact Howard, he knows his veterans.
Its notes somewhere there he has a watercooled cylinder for this.

https://www.flickr.com/photos/flattank_motorcycles/6142926538/in/photostream/
https://www.flickr.com/photos/flattank_motorcycles/6142371419/

Not entirely sure you have a 1912 model, looks earlier ?
Rex had watercooled engines from 1906...

If anybody wants one I´ve got a BSA Beagle surplus to requirements.And a brand new engine for an Ariel 3.

Perhaps it goes, without saying, that designs need to be sensible, reliable and non-maintenance intensive.
Without being too quircky.
Thinking cheapskate produces cheapskate ??

Although commercial success may just be a lottery.
http://assets.amuniversal.com/9d4ab0b076540132bac7005056a9545d

Motorcycles are motorcycles Doug, and all are welcome here.

KO reportedly made approx 15,000,000 of these engines,
so thats 15 million 15 year olds mobile on their mopeds.
Oh joy, o freedom. ?
With possibly 3 or 4 change of owners each, thats a lot of 1st time motorcyclists. ?
Now why didn't the Brit factories think of that....
This one looks quite substantially built, so they were made to last ?

All I could find with a quick search is that the KO is
produced near Leningrad  in KO = Krasnői Oktjabr factory.
So the engine at least is Russian, and the rest is likely to be too. ?
It seems there was a Latvian Moped Factory "Sarkana Zvaigzne"
which may make it a SZ-50 moped with KO 49cc engine.

There were apparently a series of those engines, from the 1950s,, with rotary valve inlet,
and lately the Chinese have been doing newer more bicycle type versions - but without the rotary inlet.

Not knowing values in Sth Africa, its likely to be worth what someone will pay.
Which is stating the obvious, but unless it is running well, its value is not going to be huge,
mopeds have a following though and its certainly unusual.
Cheers.

Isn't Motosacoche literally an 'engine in a suitcase'  or similar ?

These were popular clip-on type engines for ordinary bicycles.
Add clipon engine, the pulley to the rear wheel and go...

https://buyvintage1.files.wordpress.com/2011/11/motosacoche_3.jpg

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...

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.

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...