1935 ES2 magneto

Norton Spare Parts Lists of the 1930s did not include, with the exception of a few consumables, any information relating to Lucas parts and the factory records are likely to simply state 'Magdyno'.

Lucas for their part were masters of supersession and if a complete unit was required would simply supply the latest spec.

Your engine will have the inlet cam driven via the valve train and thus a clockwise magneto (and anti-clock dynamo). At this time it would have been the ring-cam MSL1 type. The dynamo would certainly have been of the 3rd brush type (and best converted or substituted).

Visually it would have had the 'scalloped' drive-end cover.

Machines from about 1937-on would have had the face-cam MO1 and these are easier to find, not least because they were also fitted to the 100,000 WD16Hs. Once again, clockwise drive is important (although they can be converted) and Norton were unusual in having the pick-up on the cylinder side. The base plate will need to have the four-screw fixing.

If using an Mo1, then visually the post-war versions are 'cut-away' under the dynamo body and always had the flat drive-end covers.

Brightspark Magnetos has a pdf of the later Lucas catalogue on his site which is useful for illustrations.

Many of the mag specialists will rebuild a donor unit to the correct specifcation.

Nick, I'm far from an expert on Magdynos, but in the absence of any published sources, I have tried to understand the Norton applications based on what I've seen and the odd period reference.

The photo below shows a Magdyno fitted to a 1935 ES2 - Instruments of this period do not appear to have had the later aluminium (brass in wartime) specification plates but were stamped along the leading edge of the base flange.

They are generally dated, although not always with the '3' of 1930-something...sometimes just a month and final year digit. If yours has a date that appears to be two or three months before the machine production then it is most likely to be the original.

The mag body shouldn't have a flat top but should have a recess along the full length. Post-war models have a gap underneath close to the drive end.

Points seem to be the 470609 type. A 'Google' of this reference appears to show that this is the same as used on the K2F so they should be fairly easily available.