Now that I have some time on my hands I thought I would share a picture of the oil filter I have just fitted to my Gold Flash. I machined an oil filter housing at work, made a mounting bracket and utilised the lug under the swing arm as the attachment point. I just about got away with cutting the existing return pipe and re-crimped the ends with some fuel feed elbows I bought online. The filter is a Mann W77 but the 2CV type will fit-just. It's a neat mod, unobtrusive, easy to change and keeps the rest of the bike original. It's reassuring to know that the oil is as clean as possible so the change interval will probably be annual now.