Hello years ago when I was a kid of about seven or eight back in the early 1960's my brother picked up an old motor bike from an old chap who was throwing it out for scrap. it had a ridged frame and a single sprung seat and a half moon speedo it had no engine and we used to take it in turns pushing each other around on it I often wondered what make and model it was, as any one any ideas as to what it was ???
Not a lot of info to go on but based on the date, speedo, seat and frame descriptions and considering the number produced it could well be a BSA D1 125cc Rigid Bantam. Your best bet is to search the internet for a few images and see if they match your recollections