I got a frame a couple of weeks ago but I'm not too sure as to who manufactured it, I was thinking possibly Matchless/AJS because there’s a tank bracket/fitting which is pretty typical of them but I’m not certain. It's a bolt on hardtail section and the front frame doesn’t split into two. From what I can decipher the numbers on the downtube, which would be directly under the saddle, read 23 then directly below that is 82/18462. The frame is fairly small, probably capable of fitting a 250 or so engine in. I've tried to look for models with similar frames but I haven't found any that have the engine/front frame sitting lower than the bottom hardtail mount. I know it’s not much to go on but any help or a point in the right direction would be much appreciated. Sorry there’s no pictures, I’m not too sure how to upload them yet. Cheers! Sam