Thank you all for help and information.
I think I'll clean it and polish it and keep it for its sculptural value.

cheers: Ottmar Dietrich

So now I found out how to add Photos.
Maybe its easier now to tell me something about this engine.
I saw no green colour at all. So maybe it wasn't an army motorcycle.

Your's sincerely: Ottmar Dietrich

Dear Mr. Nash, thank you for the information. Unfortunately there is no frame and bike, only this engin.
greetings from Germany: Ottmar Dietrich

Dear Members of the AOMCC, I got an Ariel single port engin R.H. 350 . Engin number is: BH 9 34 Does that mean that this engin was built in september 1934 ? I could not find a BH series.!? To which motorcycle belonged the engin. R.H. -- Red Hunter? As parts are missing -- where could I find a drawin...