Electra rear guard arc length

Michael,

My measurement of the mudguard arc length is 48 and 3/4 inches. (This is measured on the bike and is measured diagonally avoiding the rear number plate, rectifier, etc.) Hope this helps.

Wow Michael,

You're really getting into these lightweights.

The Electra rear mudguard/fender is the same pressing as Navigator or Jubilee. So if anyone has one of these handy, they could give you the arc measurement you want.

Virtually impossible to measure arc when mudguard fitted to bike, otherwise I'd venture out through the frost to the garage.

Peter

Only having the one Electra, I have no idea if it's standard or not. My rear mudguard is about 3/4" clear of the swinging arm cross tube, and just clears an oil filter a previous owner has added behind the vertical channel section. However, if my mudguard was 3/4" longer it would be very, very close to rubbing on the tyre.

I have just measured my Electra rear guard. Yes it is NOT easy to measure on the bike, but I came up with 49 1/2 ". So there.

Then I also looked at the Wipac (?) regulator fixing. Mine has been bolted on with two bolts up/down on the mudguard. While the one above has three bolt holes, when I looked in greater interest at my regulator base it has a plate converting the regulator 3 holes to two holes for my mudguard. So once again Norton modified things way back in the early 60s.

While on about the regulator, when monitoring the battery voltage I found that often the battery was being under charged, then switching the headlight on caused the extra charge to cut in, now we were over charging. No sense of proportion! So changing to Zener regulation some years ago cured that problem. Now no zeners one would have to install a Regulator/Rectifier.

Michael,

I am able to confirm from period documents the details of 24860.

When the Electra mudguard is rested on the rear curved end and the front flat edge the total height from the floor to the top of the guard is 16.5 inches.

The width of the profile is 5 1/8 inches measured between the flat sections.

One side of the profile is flattened to clear the chainguard and the the width between flat sections here is 4 11/16 ins.

If your mudguard has been shortened at the front you will be missing the two 1/4 inch vertical front mounting slots.

2 3/8 inches apart, 5/8 ins long, centred 7/8 ins from lower edge.

The arc length from my data is 49.34 inches measured from front edge, over the guard, to the radiused rear edge.

Actual mudguards may vary on tolerance, but this confirms the 49.5 inches measured by other people.

My Electra came to me with a dominator mudguard, fitted with the three tabs and chromed. The width was greater so the mudguard mounting spacers had been shortened. The height was greater so the seat rear mounts had been extended to permit fastening of seat. Rusty beyond hope. I paid a kings ransom on a well known auction site for a near perfect example, unrusted, from California.

Hope this helps you. And maybe others.

Peter

As usual - I have not monitored this channel for a few days and missed this whole discussion. Sorry guys! Please use the Lighttwins email address for quick answers, which I can then paste here.. Luckily, Peter Holland minitors this channel for us and can be guaranteed to provide a good answer.

Sadly, I have seen too many Lightweight rear mudguards sacrificed to fit Dommies, with 3 results as already discribed above. 1) The Electra (and Jubilee/Navi) mudguard is less wide than the Dommi - and 2) The lower front of the mudguard needs removing to clear the Dommi swing arm and 3) the chain detent then appears too high above the chainguard.

And, as Peter found - going in the opposite direction is even harder, as the Dommi mudguard is wider and possibly taller, yet not long enough at the front.....

The Dommi rear wheel & tyre are 3.50 x 19", whilst the Lightweights use 3.25 x 18" - narrower & smaller!

Jubilee Navigator & Electra mudguards are all the same pressing, but there are differences: Birmingham built bikes used a fully enclosed Number Plate holder, held in place by two studs/bolts across the rear, with a 3rd hole for the tail light wiring. Once they moved production to London in 1963 - coinciding with the Suffix Letter appearing on Registration plates, AMC introduced a newer Number Plate holder that was more open & wider. The AMC unit is fixed by three bolts/studs - one at the top & two lower down, plus (again) a 4th hole for the wiring. The Electra mudguard has 3 tabs on top (as already mentioned) to mount the voltage regulator (which is best by-passed by a modern regulator/rectifier - remembering to take the original rectifier out the circuit as well. Talk to Myself or Al Osborn about this)..

Also, there were soft metal tabs under and along one side to hold the twin lighting cable - stop & tail light. I have found it helpful to add a 3rd wire to provide a proper Earth return back under the seat - instead of relying on a hit/miss earth through layes of paint!