Wednesday, 11 October 2017

A few little updates

So, a two weeks is a long time with no blog posts, but I have been out and about and done some of the little jobs. as you will have seen, I've updated the regulator and all is working fine now. Unfortunately a 20 mile road test a few days ago revealed that all was not well with the old Italian dip switch that came with the bike, in that it appears to have several extra positions, most of which give no light at all. More on that later.

Still, the bike is going well. I have several old, original grease nipples courtesy of that nice Mr. John Mitchell of the AOMCC, and these have allowed the girders to be greased properly:


The girders are now bobbing up and down with every little ripple in the road. Secondly I've cut a screwdriver slot in the brake torque arm anchor to help me tighten it up:



This modification was inspired by the W/NG that lives at the Norfolk Motorcycle Museum, in North Walsham:


I've also had a look at the primary chain, which I found was tight at certain positions. I've backed that off a little and added some SAE 50 to the chaincase - everything sounds happier in that direction now.

Friday, 29 September 2017

Updating the Lucas MCR1 Voltage Regulator

The little Lucas MCR1 is used with the short Lucas E3 dynamos, like the one fitted to my W/NG.

I like my bikes to look period, but I don't mind updating them to improve performance if there's no visible sign of it externally. The MCR1 was not working, and since I have a similar electronic regulator on my SQ4, which has been looking after my charging system for years, I have no qualms about updating this one.

The update to the SQ4's MCR2 Regulator is shown in a previous post. Today we are looking at the MCR1.

I am going to fit a modern V-Reg 2b dynamo regulator which is designed to replace the mechanical regulator with modern, reliable semiconductors, 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. 


New features of the 2b 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.
Mine came from AOServices, who manufacture the V-Reg. You can buy them from a number of other suppliers, but Alan Osborn at AO provides a fine customer support service here in Norfolk. when you order your regulator, you must specify the polarity - a positive earth regulator uses different components to a negative earth regulator, and yo cannot convert them. However, the same V-Reg 2b will run a 6V system or by cutting a simple wire link will run a 12V system.

Here it is, with the original 1942 MCR1 quaking in the background. That little green wire is the 6V/12V link.


To get inside, undo the wire clip and remove the cover to reveal the coils & terminals. We'll be removing those coils in a moment:


Here's the underside, showing the two screws holding the bobbins in place:


The cover is stamped with the month and year of manufacture:


Now to start work. The original D terminal screw is soldered in place - peel the solder away and remove both of the visible screws:


The coils will now be loose. Cut all the wires to each of the terminals, being careful not to damage the terminals:


Lift the coils away:


Remove the clip. It's going to get in the way:


Clean up thoroughly. This is a glass brush - it's quite abrasive and does a fine job of cleaning the terminals and the muck around them. Clean the rest down with a spirit wipe.


Take a small soldering iron (this one is a variable 60W iron) and remove the solder and any remaining strands of original wire from the terminals. You can use a solder sucker if you need to.


Then clean the terminals with your glass brush or a sharp knife. Make sure the holes are clear.


Cut off the eye underneath the regulator. It's connected to the D terminal - you don't want charging voltage escaping into the rain. It easier to do this from above, unlike my picture:


Now, the MCR1 is a lot smaller than the MCR2 we upgraded for the SQ4, and the mounting for the V-Reg 2 needs to change. Here I'm using four adhesive pads to stick the V-Reg to the Tufnol insulated base of the MCR1. Don't stick them down yet.



So here we have bared the wires and carefully threaded them through the holes in the correct terminals. BE CAREFUL! you don't want to get this wrong and destroy your new regulator. Bend the bare ends to align with the terminal and increase the strength of the joint.



Now solder the wires in place. Make sure you have heated the terminal effectively, so the solder flows cleanly and wicks into the conductor strands. Don't melt the solder directly with the iron, but let the work heat the solder - that way, you know the wire or terminal is hot enough to make a good joint. I'm using electricians cored solder here:


Coil the wires above the regulator such that they stay within the MCR1 cover, and retain with a small tie-wrap. We don't want to introduce a fatigue failure or have these wires trapped somewhere.


All done:


Finished, with no visible changes:


And the bike is charging:


Wednesday, 27 September 2017

Misfires & Winter Jobs

I've tracked down an annoying misfire that may be of help to others. After a while, my Square starts to idle very roughly; so much so that I have had the carb apart for cleaning several times. The misfire seems to occur when I am on the way home, and I thought that it was happening when the engine was hot.

I've started to realise that it is down to the No. 3 plug terminal. When the engine has been running for 50 miles or so, there is enough vibration to back off the nut on the plug, with the result that the plug terminal sometimes shorts against the inlet stub...





Better HT cable routing required. I also noticed that my HT cable routing fouls the Bi-Starter mechanism...

It's time to think about winter jobs on the bikes, especially as the W/NG is nearly done and I will have at least two to choose from. For the SQ4 these are:
  1. Fix the speedo and get the blurred dial replaced
  2. Get a new slow-running screw for the Solex
  3. Decide on removing the indicators or not - I need to do something, because the indicators are regular tungsten bulbs and the load causes the LED headlamp to flash with the indicators. This is a bit disconcerting at night...
  4. Replace the front wheel bearings with sealed bearings
  5. Replace the front inner tube which leaks slowly
  6. Look at the brakes again as they bed in
  7. Make a new tool roll
  8. Fit a couple of transfers
  9. Change the oil tank for the one with a good filler neck thread
And for the W/NG:
  1. Grease the forks & replace the missing nipple
  2. Maybe replace the fork bushes
  3. Tighten the brake torque arm anchor or weld it in
  4. Make a T-bolt for the exhaust clamp
  5. Adjust and lubricate the primary chain
  6. Have a look at the clutch
  7. Change the regulator to a V-Reg
  8. Fit a couple of transfers
All good fun! And if I get a bit of bench space, and any spare time after that lot, I might start looking at the various welding jobs on the Huntmaster tinware...

Monday, 25 September 2017

Old Warrior Back in Action

So, over a year since the Old Warrior arrived on our shores, I've been out for the first proper ride and what a cracking bike it is. The gearing is very low as expected, but everything is working (except the voltage regulator which I knew about), the engine starts easily and pulls very well and the handling is rock steady.


I've never ridden a rigid bike before, but it feels more secure than my Anstey-frame SQ4 and my plunger Bantam. I've not hit any bumps yet, cranked over, so perhaps I've not really experienced the darker side of rigid bike handling but right now it feels good. I've not seen much movement from the forks - perhaps they are very stiff. They certainly need a session with the grease gun. I have the tyres set at 24 psi at both ends, which feels fine at the moment.

The brakes seem OK - better than the SQ4, but then this is a much lighter bike. Good feel and quite powerful, though there is a clonk from the torque arm. Clearly that's loose & needs sorting out.

The engine sounds a little rattly and is burning oil off the head - there has been some leaking from the rocker feed studs, which I have nipped up, and there is oil in amongst the rocker boxes. This is merrily burning off but I am not sure if it is still leaking. Time will tell. The primary drive sounds like the chain is too tight, and the clutch may be dragging a little, but the oil is returning happily.

So here is the job list:
  1. Grease forks & replace the missing nipple
  2. tighten brake anchor
  3. primary drive thrashing
  4. clutch dragging
We'll see where the next trip takes us!

Oil burning off the cylinder head
Same bike, same place, a few years earlier?


Friday, 15 September 2017

MZ Frame coming along

The TS125, in another part of Norfolk, is coming along slowly. This week, some reassembly and some painting.

Front mudguard:


Headlamp brackets and fork shrouds:




Here's the centre stand spring being stretch in time-honoured fashion



Back on the frame:


Spanners removed and the stand is back in action:


Fork yokes back in:


SQ4 - Oil Line Mod

I'm having a few issues with oiling at the minute, some of which are due to my own stupidity and some of which are not.

I have had persistent problems with the feed union to the cylinder head, which despite re-tightening on several occasions has always backed off after a few hundred miles. Seeking advice on this on the AOMCC forum, Nev Hunter from Australia pointed out that it was the fibre washer I was using that was at fault. This area gets so hot that it will cook a fibre washer...


In this location you must fit a copper washer:


The second problem was not of my making. There are two oil lines leading up to the cylinder head from the crankcase; from the front main bearing as shown in this diagram of the 4G, and from the rear main bearing, a banjo under the timing cover on later bikes. The assembly consists of two lines _ a 3/16" line for the gauge, and a 1/8" line for the rockers which seems illogical but the 1/8" line is there to choke the feed to the rockers and to maintain back pressure at the main bearing. Problem was, several assemblies are out there that are the wrong way round, which results in over-oiling to the rocker box and a gauge that under-reads (since the oil pressure to the rockers is lower), so we will set about fixing the problem.


4G Lubrication System

You need to take the tank off to have a look.


Here are the oil lines - the 1/8" pressure gauge line and the 3/16" rocker feed lien. We are going to swap these around:


Here I've cut the old 3/16" rocker feed line and fitted a 1/8" equal union, which will mate directly with the existing line to the gauge:


Using the remains of the existing 3/16" rocker oil feed, just the last few inches to the head, I've fitted a 1/8" nipple & nut to mate with the old gauge line coming from the double banjo under the timing case. In this picture, I'd kicked the engine over to prove I had oil coming out of those lines:


I took this picture after the first road test, when I discovered that the rocker box soldered joint had failed - poor penetration caused by bad fluxing or low heat: