W/NG - Small Jobs

 A bit of workshop time this afternoon gave me the opportunity to complete some long-standing jobs on the W/NG.

This first is quite a simple one. There's been a leak from the rocker box oil feed for years - actually ever since I've had this bike. It's never had an acorn nut and in all the time I've been running it it's had a plain nut in this position which obviously won't seal the banjo. This afternoon I made a new acorn nut using a piece of suitable stainless steel hexagon bar finished with a specially ground form tool. 

Hopefully this will stop the leak!

Next up, a part that I didn't even know was missing until a chance post on the AOMCC forum. This little bit of bent sheet stops the field stand from moving upwards too far - it means that you can grab the stand with one hand whilst sitting on the bike and fit it neatly into its spring clips. Essentially the little bar guides the field stand into position and all you have to do is push it into the spring clip. 

It's made of a bit of 3 mm sheet, drilled for 7/16 and bent to shape.

Here it is, painted and in position.

Next is the new Lucas U39 switch - I have the proper one at last, including the 'T' position which illuminates only the tail lamp.

This is a picture of the underside of the existing switch, showing the position of all the wires.

I didn't get to finish this part of the job, so more of that later.

FH - dishonourable discharge

 So after a few weeks on the bench, dealing with the wet-sumping and the fact that I seem to have forgotten how to start the Huntmaster, it now seems to run ok. Only problem is that it won't charge.

First suspicion was some wiring problem, or a failed regulator - crazy really, as in all the years I have used these regulators and wired my own bikes I have never had a problem. With the bike idling I had a look at the dynamo to see if there was anything coming out of it. I saw nothing. Zero volts. Nada.

I had a bit more of a poke around with the multimeter and eventually realised that the problem was a bit more fundamental than even the wiring of the dynamo - it wasn't actually turning! If I turned the armature by hand from the commutator end it was clear that there was actually no resistance - mechanical resistance I mean.

Next step is to turn to the other side and have a look at the drive chain. Normally this is suspended between two sprockets, one on the idler spindle and one on the dynamo - it's not supposed to be lying in a heap at the bottom of the timing case.

I poked around in the grease and pulled out a chain which still had the broken link on the end. Fortunately a bit more poking around found the side plate so I could be satisfied that I had all the broken bits and nothing was going to disappear into the engine and cause some monumental failure.

I bought this chain from Draganfly - and of course I mailed them to say that it had broken after 250 miles. They were excellent and had a new one in the post the same day.

The expert opinion from the AOMCC FB pages is that the chain was probably too tight. There is a recommendation in the Owner's Guide that it should have an 1/8" to 3/16" play - I've always had a bit of a problem with determining chain play and thinking about it I am undecided as to whether the measured play is stretch, with the links tight, or play with the links loose. I am going to try and fix this with that play being given by looseness in the links rather than by forcing the chain to deflect by the given amount. 

The little puller makes short work of removing the idle pinion dynamo sprocket, and attempting to replace the chain without moving the dynamo suggests the chain was way too tight.

It's charging merrily again now and we'll see what happens - if it fails again I might buy a belt drive kit from SRM.

W/NG - on the bench

 With the Square Four away it's time for the Huntmaster to step up and become go-to bike. The W/NG is going on the bench for a bit of a look around and some little jobs .

It's quite oily and I know that the decompressor is still leaking. What I didn't expect was to see that the leak appears to come from the main decompressor body and not from the spindle - it appears that the Dowty washer isn't doing its job and perhaps that is because the mating surface isn't as flat as it might be. I've cleaned up the nut and mating surface and relaced the Dowty washer with a new one, as I don't have a fibre washer of the correct size.

I've also replaced the (missing) gasket in the exhaust inspection cap - see that drip?

On a club run a couple of years ago, the horn fell off and it's retaining bolt was replaced by a 5/16 screw from the spares kit. I've replaced this with the proper 3/8 screw and I've also moved the horn bracket a little bit so that the terminals don't touch the engine plates and the horn body doesn't press the cable against the frame. The horn is now free to vibrate properly.

I've taken the opportunity to reroute the cable as well.

There are always tiny little things that bug you about a bike, particularly one which is in patinated condition like this. The washers under the headlamp bolts were very large and unsightly being chromed. I've replaced these with some rough old washers of the right size which look a lot better.

I've stripped the carburetter and cleaned the idle ports, but I didn't really find anything.

In other news, the Huntmaster has most definitely wet-sumped. There's probably a pint of oil here in this pan which I drained from the sump, being unable to start the bike. You could feel the oil in the crankcase being churned up when you kicked it over.

W/NG - it's home!

 Well, it's home!

Today I took the SQ4 down to my son's house for a holiday, and brought the W/NG home - a round trip of about 60 miles with a bit of extra lane-thumping. I'd forgotten what a laugh it was.

For some reason it's refusing to idle, and the decompressor is still leaking...

W/NG - broken MT110

 Checking over the W/NG yesterday whilst babysitting the two youngest revealed a bike that started, whose lights worked with a new battery but no brake light. A bit of nosing around soon found the problem - all the wires to the Lucas MT110 rear lamp were torn out of the fitting somehow. Since it's been sitting in Thomas' garage surrounded by bicycles, tools, other motorcycles, lawn mowers and the accoutrements of three small boys it's hardly surprising that it's suffered some damage. 

The problem is that I have very little time to repair the lamp before I need to ride it back tomorrow. I bought the lamp back to the workshop to give it a dose of looking at.

The first job was to sort out a way of replicating the contacts in the lamp base. I discovered that these boot lace ferrules I had in the terminals box have a slightly belled end and you can thread a new wire through, spread the strands out and add a blob of solder.

That's the first problem fixed.

Next is to sort out the earth connection. I thought that the original earth wire was soldered to the outside of the lamp holder - turns out I was wrong about that but what I planned to do was put a washer type fitting inside the lamp base and solder a wire to that, like this:

I eventually found that actually the original wire was soldered to a brass washer which was still there, and which I could have used. Hey ho.

The next bit, and apologies for the terrible picture, was to add some heat shrink to the rear lamp and brake lamp terminals to add a bit of extra strength. This is actually a bit long and inhibits the deflection of the connectors as they go into the bulb holder. 

Reassembling the lamp left me with something that didn't work at all. I pulled it all the part again and realised that the inside of the bulb holder was corroded and I wasn't getting an earth connection. The Dremel fixed that along with a bit of sandpaper.

So that left it all working again and hopefully I can bring the bike back tomorrow. I might pull this lamp apart again and use the original brass washer, since the spring is not in very good shape and is rather weak.