When I was picking up another bike recently the chap was throwing out an old compressor and asked if I wanted to take it. Not being one to see old shit dumped I took it home. Closer inspection suggested the air pump was an engine converted. Many hours of trawling through pics on the net turned up it is a 1926 Matchless model R engine. It's in good condition as it's full of oil and only pumping air, although some bits are missing. Anyone got or know someone that has one as I'm wanting to build a bike around it. Parts needed - everything. Any info on these, such as what other models used same cycle parts etc?