SPARKING PROBLEM
Poor Tim Wait; the day after having his entry confirmed for the VMCC Banbury Run, his 1930 Royal Enfield BL30 stopped sparking. “The magneto is apparently an ML CK1, can you help?”
Oh dear! Trouble is that mag rebuilds are a long job and all the good repairers I know have long waiting lists. I built a ‘square ML’ CK1 recently for a Sunbeam – they are very hard to find, but any original mag is likely to need rebuilding, whether or not it sparks on the bench. I think the BL30 originally used a Lucas magneto, which would be easier to find, but the same still applies.
The only good news is that magnetos are a fairly universal fit; you need the right direction of rotation (it’s usually stamped on the drive end) and there are two possible shaft heights, but otherwise even a post-war unit could probably be adapted to fit and get Tim on the road for the run. It’s also worth looking at his own mag, though. Carbon build-up on the HT slip ring can accumulate and cause shorting, so that’s worth cleaning, with a rag poked through the hole where the HT lead pickup is fitted (put a piece of card between the points though or you’ll get a shock). Worth cleaning/setting the points too and make sure the centre bolt on the points plate is clean, it forms the electrical connection for the low tension circuit. But this is probably clutching at straws; it sounds like it needs specialist attention.