<p>Reviving a century-old magneto</p>

You would think that Carl Kenney of Vintage Magnetos has seen it all before, as one of the UK’s leading magneto specialists. But such is his passion and unrelenting enthusiasm that everything that is brought through his door at The Western Tanker Sheds of Bicester Heritage is looked upon with wonder.

One of his current projects is a little more special, though: a Bosch from 1905. “I was the first person to ever take it apart since the day it was built,” he says. “It’s built in a way that I have never seen on any other magneto because the approach to fitting the condenser is totally different. Bosch standardised things really early on so they all follow the same script; whether it’s on a motorbike, car aircraft they are the same. This is unique.”

Carl dated the magneto, which is from a Norton motorbike, by referencing the framed sheet in his office of early serial numbers. “They only started numbering them in 1903,” he adds. “It’s the oldest one I’ve rebuilt. It’s really nice that it’s not been touched.”

Other details hint to its age, too, as Carl explains while carefully dismantling: “The condenser is built into the top section and still has the guy’s initials on it in pencil. Everything inside is engraved with a part number or signature, probably by one man.”

That made this something a of a journey of discovery, because, as he points out, no drawings survive or are to hand. The cam ring, for example, which needs to be to be snug for the magneto to fire properly, has worn and is no longer round. A new one had to be fashioned by hand and eye and aged to match. “The owner likes things to look just right and untouched from the outside but perfect inside,” Carl says.

“The nice thing about this is that I’ve put a modern condenser in where the original was. The easy option would be to put it where it would be in a more modern armature, but I’ve used all the old fixings and found a modern condenser that can fit in its place. So although it’s restored, it’s as close to the original that it could actually be, using the original bracketry but with modern reliability built into it. As much as you can build into a 115-year-old part…”