Electrical problem.

[Gelandestrasse]

FWIW looking at the corrosion of the red wires in your picture, you are likely to have corrosion in all the in-line connectors under the tank. I had good results with a small container (top off a spray can) of vinegar, remove the terminals from the connectors and submerge them in vinegar overnight (I used tape to hold the container to the bike and also to force the terminals to stay submerged). With additional help from a brass wire brush, you can make the terminals scrub-up very nicely indeed. Then reassemble with a light covering of (I use vaseline) some proprietary terminal grease.

Also, I would advise you return the wiring to standard (eg, don't test it with the main earth disconnected) as you will be chasing your tail with spurious faults.

 

[VAL. H.]

FWIW looking at the corrosion of the red wires in your picture, you are likely to have corrosion in all the in-line connectors under the tank. I had good results with a small container (top off a spray can) of vinegar, remove the terminals from the connectors and submerge them in vinegar overnight (I used tape to hold the container to the bike and also to force the terminals to stay submerged). With additional help from a brass wire brush, you can make the terminals scrub-up very nicely indeed. Then reassemble with a light covering of (I use vaseline) some proprietary terminal grease.

Also, I would advise you return the wiring to standard (eg, don't test it with the main earth disconnected) as you will be chasing your tail with spurious faults.

Lots of corrosion in the connectors, but nothing really bad. That red multi wire block was by far the worst. All the connectors have been pulled open, cleaned and tested. So far as my limited experience of electrics goes, all is good in the loom.

The New Diode board arrived today. I decided to go for the more modern version. Fitting was easy, plug and play with clear instructions. It's not produced a cure to the problem though. Never mind (*&%^$£&***). At least we now know that the diode board is good. I'm in deep enough now not to stop and am now as certain as I can be that I'm looking at a module failure. So I'll fit a new regulator and maybe a new Ignition amplifier after that. If none of that works, I'll have to submit to a new loom. F..K At this rate I'll be end up doing a full restoration........

 

[ChasF]

I wouldn’t blow money on new modules. Easiest thing is to disconnect them and see if anything changes. I still think it’s a problem with the ignition switch. Even a new loom may not be an instant answer as I wouldn’t be surprised if there is more than one fault.

Edit ignition amplifier is very unlikely to cause this sort of fault - just pull the plug out

 

[kirby morgan]

This may help your fault finding.

 

[VAL. H.]

I wouldn’t blow money on new modules. Easiest thing is to disconnect them and see if anything changes. I still think it’s a problem with the ignition switch. Even a new loom may not be an instant answer as I wouldn’t be surprised if there is more than one fault.

Edit ignition amplifier is very unlikely to cause this sort of fault - just pull the plug out

Ignition switch. Is testing it as simple as removing the red and green then touching them together?

This may help your fault finding.

Thanks, Much easier to make sense of this than the Haynes wiring diagram.



Val.

 

[Nin]

Your wiring diagram should show which wires connect at different switch settings. I’d remove the switch and use wires to recreate the connections at each switch setting. Alternatively you can use your multi meter to check the switch outputs.

 

[ChasF]

The simplified wiring diagram posted by kirby morgan is helpful and much easier to follow than the one’s I’ve been looking at. It might be a good starting point to connect the red and green wires at the ignition switch, see what happens but before much can be done the brown wires will need reconnecting. If you can reconnect the brown wires and there is still some signs of life (and no smoke or burning smell) then probe around with the multimeter and check there is 12 volts at all the accessible points shown in that simplified diagram - starter motor, diode board (before connecting the ignition wires) and kill switch etc.. If there still a problem start by unplugging stuff not shown on the diagram - relays, lh handlebar switch, headlight etc.

There’s a mass of troubleshooting info on the Snowbums site what may be useful if you can navigate your way around it!

 

[VAL. H.]

The simplified wiring diagram posted by kirby morgan is helpful and much easier to follow than the one’s I’ve been looking at. It might be a good starting point to connect the red and green wires at the ignition switch, see what happens but before much can be done the brown wires will need reconnecting. If you can reconnect the brown wires and there is still some signs of life (and no smoke or burning smell) then probe around with the multimeter and check there is 12 volts at all the accessible points shown in that simplified diagram - starter motor, diode board (before connecting the ignition wires) and kill switch etc.. If there still a problem start by unplugging stuff not shown on the diagram - relays, lh handlebar switch, headlight etc.

There’s a mass of troubleshooting info on the Snowbums site what may be useful if you can navigate your way around it!

Found it.

It was the kill switch. One of the two wires supplying the feed has been roasted, gone brittle and broken in two on more places within the cable. When I took the switch apart last week I tested all the local connections and missed the wire to plug it seems.
I'm unsure weather to solder in a new wire or just buy another switch. It's a very small contact surrounded by plastic. Though I might have a go, and then buy another when I've melted too much of the existing one.
For now, I have put in a new wire, but the top connection sits just inside the housing and prevents it being properly secured.



All working as it should now.

Thanks everyone who helped with suggestions and information, much appreciated. Now back to getting this old thing out on the road again.



Val.

 

[r100gser]

Have a read of this it might be helpful.

https://robfrankham.com/about-earthing

 

[Beemerboff]

Have a read of this it might be helpful.

https://robfrankham.com/about-earthing

When it comes to electrics just about everything he posts is worth printing , framing and hanging up on the workshop wall.
Good you found the old, brittle and broken wire, but you are probably going to find more. And more.
Which is usually what prompts folk to finally decide a new loom is the way to go1

 

[tuftywhite]

One of the reasons I had my g/s restored was that I encountered electrical fault after electrical fault. At the time, it was 30 year old wiring on a bike that had been kept outside all year round.

The wiring just kept failing in different places. I'd get a few months riding and something else would fail. Along with the frame starting to go rusty I bit the bullet and had a restoration with a new loom.

That was 12 years ago and everything's been fine since (touch wood). A new loom would certainly give peace of mind for a low(ish) cost, considering the issues you may have in the future and reliability issues if you're away from home.

 

[VAL. H.]

Have a read of this it might be helpful.

https://robfrankham.com/about-earthing

Looks useful, I'll have a read of that later.

When it comes to electrics just about everything he posts is worth printing , framing and hanging up on the workshop wall.
Good you found the old, brittle and broken wire, but you are probably going to find more. And more.
Which is usually what prompts folk to finally decide a new loom is the way to go1

One of the reasons I had my g/s restored was that I encountered electrical fault after electrical fault. At the time, it was 30 year old wiring on a bike that had been kept outside all year round.

The wiring just kept failing in different places. I'd get a few months riding and something else would fail. Along with the frame starting to go rusty I bit the bullet and had a restoration with a new loom.

That was 12 years ago and everything's been fine since (touch wood). A new loom would certainly give peace of mind for a low(ish) cost, considering the issues you may have in the future and reliability issues if you're away from home.

It was just that one wire that seemed to have been roasted/ got hot, but no melting. The one that runs along side where fine.

However a new loom is on the cards. But I'll wait until I'm back at work after, my broken leg of last September. Until then it's back to plan A, refurbishing the rig and building a new tub. Something a little more suitable for trail riding.



Val.