BSA Bantam D1 project bike.
Frame number: BD2S 71085
Engine number: DD 12791
This makes it a 1960 direct lighting D1 model. The engine and frame numbers are both close enough together to assume that they match. There are however no documents with the bike.
Obviously the bike is incomplete so here's a list of what you are getting: pair of wheels, frame, forks, front mudguard, petrol tank, engine and carburettor, chainguard, centre stand, rear brake pedal, handlebar and levers, footrests.
The engine turns over. Would perhaps make a good starting point for a Bantam trials bike project?
Delivery can be arranged. Expect round about £80 for most of England & Wales. Less if you are close to Bournemouth and a little more up to Scotland.