Sunday, 15 June 2014

Monday, 9 June 2014

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!

Sunday, 8 June 2014

It's Show Time Again!

The day dawns bright & shiny for the annual Sheringham Classic Car & Bike Show, part of the Sheringham Carnival celebrations.

A few bikes this year and even less photos! Beattie, my Bantam in amongst some Ducatis:

A very nice Triumph

A BSA C12 - a local bike, but I don't know the chap that owns it:

A nice Matchless G2CSR:

Monday, 2 June 2014

A sunny day in June

My Square Four tank, and it does appear to be a Square Four tank (very large and of the appropriate width; large filler, pressure gauge hole) has as I said two taps (it also has a drain at front RH and no crossover pipe). What I neglected to mention (or even realize) was that the taps are forward of the tank mounts:

As you can see, on a Mk1 these are very close to the back of the rocker covers and will get frighteningly hot, I suspect. It looks a little odd; the closest reference I can find to this arrangement is a rather nice '51 KH shown in an article in RealClassic, which has two Ewarts taps in a similar location. The curious thing is, I have scoured all the KH and SQ4 parts books I can find and they all describe a single tap.

Hmm... Is this really a Square Four Tank?

So, one plan is to use a pair of Ewarts type plunger taps, 3/8" BSP into the tank with horizontal outlets. I will then make a copper/rubber tube assembly to tie the two taps together into the single inlet to the Solex. an alternative would be to blank the tap hole on the RH, and use a two-level plunger tap on the nearside - but I am not sure I have room for that.

I will need a supply of tube, nipples and gland nuts to make up this assembly - and I guess I will make a tee out of some brass barstock. I'm not sure where to buy these parts yet...

On a brighter note, she is a very handsome machine:

Max is nonplussed

Ariel do not seemed to have paid a lot of attention to the maintainability of their machines. Two maintenance items in this picture, neither of them easily accessed AND I have removed the kick start lever. More positively, the oil tank is now hooked up.

The valve timing is done, with a little help from my daughter - assembling the cam chain tensioner is not a one-man job:

And the exhaust pipes are looking good. The eagle eyed amongst you will notice the clutch dome is still off:

I have discovered however that when I straightened the RH footrest hanger, I straightened it too much and it now fouls the exhaust pipe.

More wiring done this weekend too. Horn and Lucas 529 rear light fitted:

and I am not sure what to do about the throttle cable abutment:

Sunday, 1 June 2014

Number Plate

This page is a repository for number plate pictures...

Might be useful!

The rear mudguard is 53 3/4" from end to end.

These are from Brenton Roy's 1951 SQ4:

My 1951 SQ4: