FH - wiring harness

 I'm not going to blog the complete build of the wiring harness, because I've done that a few times already for the Square and the W/NG. What I will do is show you a few details of the harness as it comes together.

This picture shows the arrangement around the back of the toolbox. From the main harness there are branches going to the horn, to the regulator, to the battery and to the stop switch.

I will probably add a series of bullet connectors to allow me to separate the main harness from the harness going to the rear mudguard.

This next picture shows the main earth cable to the rear which splits into three near the indicators. There is a soldered splice under that heat shrink.

This picture shows the harness going to the rear of the bike with that soldered splice and the wires to the indicators and the rear lamp all covered with PVC sleeving, with a heat shrink section around the joint.

The bike is running an original Lucas 564 which needed to be rewired. I've replaced the cabling and used some heat shrink to provide some wear resistance where the wires go through the rear of the lamp. The connections to the bulb are blobs of solder flattened on the linisher.

Here's the engine earth. This is taken back to the main frame earth which is the upper of the two oil tank bolts. I need to clean the Wellseal off!

For the record this is how I have terminated the magneto kill switch. There is a length of cable, covered in heat shrink, passing through a small length of fuel line which sits neatly inside the thimble nut on the end of the magneto. This end is now weatherproof.

The other end of the magneto cutout cable is soldered into a push button at the handlebar. The joint is hidden by a piece of PVC sleeving pushed over the button - I didn't have any suitable heat shrink to bridge these two sizes.

FH Dry Build - tail light plinth

 The FH, along with other swinging arm Ariels of the period has an unusual feature used to mount the tail light vertically - a little pressed steel plinth, part number 5611-55. Drags do a very nice replica for about £15, but they have been out of stock for a while and it is an easy thing to make.

Starting with the Lucas 564 rear lamp, we need a caliper, some plastic holes, a piece of card and a scalpel.

I used the holes and the caliper to mark out three holes in the card - one for the bulb holder and two for the mounting bolts. Then I can fit the lamp to the card and draw around it:

Next, I can develop the part around the shape of the lamp: 

Cut it out with the scalpel, using a wad punch for the holes if you have one of a suitable size. In my case, I punched the smaller holes and used a swivelling scalpel for the larger one:

Next, make some nice sharp folds with a ruler and use staples or a glue gun to fix the edges which will eventually be welded:

Now, we can do a test fit and trim the pattern to allow the lamp to sit vertically above the number plate:

With the part to the shape we want, we can undo the staples and stick the pattern to a suitable steel sheet. It's that old bread bin again, that gave us the air filter for the QR50:

I used the bandsaw to cut it out, but you can use a hacksaw, shears or whatever you have. The edges are cleaned and deburred with a variety of files.

Folding is quite straightforward using just the vice and my trusty bit of copper bar. With folding completed, the next step is to weld up the joints - most of which came together to weld autogenously. The linisher springs into action to clean it up:

After a couple of trial fits and a bit more time on the linisher, I treated the plinth to a bit of UPol etch primer before fitting it to the bike - temporarily, with a few magnets:

I think it looks fine.