FH - voltage regulator

 One of the jobs on the list is to make the dynamo work. During the wiring up process I decided to make the bike negative earth to allow for fitting of things like USB chargers and other modern accessories, on the basis that this bike will become the universal machine. To that end, the dynamo will need to be repolarized, more of which later.

Another thing that I need to do is to fit an electronic regulator to match the VRLA batteries I have fitted. The late Ariel four-strokes were fitted with a Lucas RB108 regulator, and we will replace the inside components of one of these with a V-Reg 2b from AO Services here in Norfolk.

First we remove the aluminium cover, bending back the tabs and pulling out the inner parts of the regulator:

There are two steps to removing these bits. First you can undo two nuts under the Bakelite board to release the solenoids. You will also need to remove a single screw that retains the frame of the regulator.

The next step is to cut the wires and links leading to the four terminals. It's easiest to cut these to remove the obstruction of the solenoids before you take a large soldering iron to the terminals and release the little bits of wire that are left. You can then open the terminals ready to receive the wires from the new regulator when it's time to re-solder.

The V-Reg 2b has a couple of options for retaining the unit to the base; there are two bolts supplied which fit neatly into the old solenoid holes. The next job is to route the wires to the appropriate terminals and solder them up. I like to use an old-fashioned wire lacing technique to make a small wiring harness inside the unit. The lacing is wax coated linen thread tied with a clove hitch and reef knot to hold the wires together.

All that remains is to put the cover back on and close up the aluminium tabs as best you can. Alternatively you could use some hot melt adhesive to hold the cover in place.

SQ4 - low batteries and flashing lights

The batteries on the SQ4 are now seven years old and are coming to the end of their life, as witnessed by a complete failure to start earlier this year, remedied with the CTEK charger, and a short trip out a few days ago. This one was odd - I had left it idling on the bi-starter to warm up and all was fine (though of course at that speed it wasn't charging). I then took it out and it had no power, eventually dropping onto three cylinders within a few hundred yards of the house - I travelled 1/2 a mile in all, none of it at high enough speeds to charge the battery.

Getting home, the multimeter showed my batteries were down to 5.5 V or so. New batteries are on the horizon!

In the meantime, picking up on a thread in the AOMCC forum I had bought a battery condition monitor from Gammatronix:

I've chosen to fit it in the top of the dummy battery box. It fits in a 14mm hole which I cut with a cone drill.

I've sealed it with some silicone on the outside:

It's also protected on the inside with some pvc sleeving:

Once you have fitted the battery monitor and have wired it up (even temporarily - it remembers it's settings) you have to programme it. This is by a simple sequence of button pushes. I have it set to 6V, Map #3:

There's a further map #6, which is for low current applications and shows a slow red, yellow or green blink according to voltage level.

Here is a very exciting video of a LED flashing green. Tell your friends, it is riveting stuff: 

Eagle eyed readers will see the CTEK charging connector I have fitted in the background. 

The battery monitor is wired in using a long twin core cable, so that I can remove the dummy battery box lid and lay it on the seat for battery or fuse box access.

Dry Build - Tool Box & Voltage Regulator

Last night included a bit of dry building activity around the toolbox, regulator and horn. I added the primary case and the clutch cover to understand the space and fastener requirements.

The toolbox hangs from one of the seat mountings using a bolt passing up through the top of the box, through the seat mounting and into the seat - all quite straightforward.

The other fixing point is this tab, beneath the toolbox which allows the toolbox to bolt to a mounting on the frame. This tab is shared with the horn.

Here's a puzzle: Ariel do not list a separate horn bracket for 1958 and here's why - the horn bolts directly to the toolbox tab as shown in MickD's picture below. I don't have those holes on my toolbox! The swinging arm toolbox carried a -54 part number through to the end of four stroke production, so I must have an earlier incarnation of the same part, designed to be used with an Altette and not the Lucas HF1441 horn used in 1958.

I will have to make an intermediate bracket, or modify my toolbox.

Post script, April 2019: This bracket was made here.

My Lucas HF1441 horn, for the FH.

Here's a Lucas voltage regulator fitted in position behind the toolbox - but this is the 40W MCR1 regulator, smaller than the correct RB108.

Here are two views of the large void from above:

And behind, complete with an up the nostril shot. Sorry about that.

A view from the front:

Updating the MCR2 Voltage Regulator

As I've probably mentioned before, I'm a stickler for originality, at least visually. If there is a period component that will do the job, then that is the one that gets fitted. However, I'm not afraid to modify components to make them more effective.

A case in point is the voltage regulator...

The voltage regulator I have with the machine - or the box of bits - is a 1962 Lucas MCR2 - obviously a replacement for the original regulator. While this is perfectly serviceable, it is not suitable for the sealed batteries I have fitted in the Draganfly battery box, so I am going to fit a modern V-Reg dynamo regulator which is designed to replace the mechanical regulator with modern reliable semiconductors, and can handle up to 100W at 6V and even more for the 12V version, provided the dynamo is capable of delivering this power. This device is proven and reliable and is available in Positive or Negative earth, also to run a 6V system. 

New features include: Current limit to the field winding, allows excellent performance when using a 6V dynamo on a 12V system while not straining the dynamo. Tougher electronics, with the introduction of higher energy spark suppression to reduce spikes generated by the dynamo. Improved "thermal foldback" which progressively reduces output power if the regulator gets too hot, indirectly limiting the dynamo from excessive current. Better servo loop stability, with new electronics which 'predict' when the output voltage is nearly correct and control the field current earlier.

The V-Reg 2a will run a 6V system or by cutting a simple wire link will run a 12V system.

Mine came from Paul Goff.

Taking these apart is quite straightforward. You'll need a soldering iron, a screwdriver and a spanner or two. Remove those two nuts and the screw visible in the picture, which may be sealed in with wax:

Then you can take your soldering iron, and a solder sucker, and de-solder the various joints topside. The E and A terminals need the wires de-soldering and removing; the F terminal is more easily disconnected at the frame (the top joint in the picture) and at the back (which you usefully can't see). The D terminal can be de-soldered at the copper cup around the screw from the previous picture:

You can now remove the back plate and the armatures, and you will be left with the mounting base and the four terminals. The F terminal is staying put for the moment, since I will have to cut it off (and after that there is no going back):

The V-Reg has a convenient pair of T-slots in the heat sink which are spaced so that the mounting bolts fit the hole spacing in the old base. The old 'D' terminal is also still in place:

Its then a simple matter of connecting the wires to the terminals:

We will tidy up that wiring when we have tested it!