Broken wires in loom

Tim88 · 09-03-2021, 06:48 PM

I have at last tracked down the cause of an intermittent fault on my right turn indicators. I had changed bulbs and cleaned the connector many times and the problem seemed to go away, but it was just coincidence. The real problem was fatigue fractures of the wires in the loom just behind the frame head stock. I peeled back the wrapping and found that the indicator wires were fractured, that is the white/green stripe and black/yellow stripe wires. I will try and solder them and heat shrink. My bigger problem is the crack, that is just about to part, iùn one of the two yellow/blue stripe wires that form the big black cable visible in the bundle at the top. I don't know what these are and the repair will be very tricky I fear. Loom repairs are horrible and I refuse to even consider bodge up crimping solutions. Not
looking

forward to this job but MoT due next week so have to get on with it. Any tips?

[/IMG]

slob · 09-03-2021, 06:58 PM

There’s a (sadly B&W) wiring diagram in the back of the owners manual if that helps.

Luddite · 09-03-2021, 07:43 PM

Well done for tracking down the problem, Tim. I had something similar on my M900, which would cut out if you turned the bars full right lock (made town riding interesting!).

The yellow/blue wires you mention are the power feed to the main beam so you've got one wire to the headlight, one to the instruments and one to the switch cluster.

Tim88 · 09-03-2021, 07:57 PM

Luddite,
Thank you for that. My symptoms were similar except that the indicator worked on left and right but not when the bars were central, I have recently been practising hand signals to alert oncoming traffic while I made a right turn, ah...those old timey skills! The info regarding the yellow/blue stripe is really useful..it also explains why these wires are contained within an extra thick black secondary insulation...because they are way higher current than the other wires...so I will be extra careful with my repair. Thanks.

alan s4 · 10-03-2021, 08:16 AM

Had exactly the same issue with my kill switch wire. Each time I carried out a feet up you turn (on full lock) the bike would stall much to my embarrassment.....I always imagined other bikers s******ing at my inept clutch control!

Dukedesmo · 10-03-2021, 09:17 AM

Quote:

Originally Posted by Tim88

I will try and solder them and heat shrink.

Personally I'd cut back the loom and take a section of the offending wire(s) out, replacing that whole section with new wire with a heat-shrunk joint either side of the broken/flexi part of the loom, so that the bend/movement is done on a new piece of wire rather than a repaired and, inevitably stiff joint.

You can then stagger any joints on other broken wires so that you're not adding too much bulk to the loom in one place.

A little more work involved but less likely to fail again after a few months.

Nasher · 10-03-2021, 10:09 AM

As mentioned, well done for finding it, locating that sort of thing isn't easy.

I spent a couple of years chasing faults like this on my M900 when I first brought it, but that was mainly due to bodges by previous owners, like the cut out switch on the right hand handlebar being bypassed with the smallest gauge wire I've ever seen on a bike.

Nasher.

Kato · 10-03-2021, 11:17 AM

I have a 1100evo wiring diag happy to email it to you i you PM me your mail address
it is B&W but does have the wire ccd's

I take the pdf to work usually where I can print out in up to A0 which makes life easier, but any decent stationer/print shop will do you large format print for a couple of quid

Unable to attach here as exceeds size limit...

Tim88 · 10-03-2021, 11:48 AM

Dukedesmo. I think your advice is sound regarding splicing in sections of wire so that the repairs are not at the original failure site! Every bit of flexibility is needed. Today is raining and as I have to work on the bike outside I will just investigate how far back to unwrap the loom etc. to do as you suggest.
Kato, thank you for your offer. I have the little diagram that comes with the owners book (probably the most useless microscopic black and white cryptic document ever printed!). I don't think I will need the diagram just yet as I only have the broken wires to repair at the moment, but please leave your offer open just in case. I will also check if there is a chart on my computer based workshop manual for future ref.

Finding these things does involve more than a bit of luck, although I am always suspicious of this particular area with all the flexing that goes on.....its enough to send you to the darkside where madness lies for a 'slow rebuild' involving carbon fibre, rear view cameras and bits of aluminium and bearings etc to try and engineer the problem away...not mentioning any names of course!

utopia · 10-03-2021, 12:26 PM

I second what Dukedesmo has said ... best to cut out a longer section to shift the repair to a different location.
I had a similar problem on my 750. In my case it was the start button wire, making it necessary to hold the button down while turning the steering from side to side, to get it to fire up.
It was a good few years ago but if memory serves, I removed and replaced the entire length of wire rather than have the stiff section that a repair inevitably causes.
This is not as difficult as it sounds as long as you can lay the loom out straight .. and perhaps add a little warmth with a hairdryer.
Soldering is particularly bad in this respect since it causes a rock solid stiffness at the actual repair itself but leaves the immediately adjacent section of wire with no insulation sheath and therefore with maximum flexibility ... a later breakage just waiting to happen.
However most if not all proprietary crimps are crude and nasty and are probably worse than a good soldered joint.
If you can get hold of any bare metal micro-crimps of the sort used in the original construction of wiring harnesses, these will make a super neat and very tiny joint which adds minimal stiffness (and minimal bulk) to the conductor.
Then cover that with a short section of glue-lined shrinkwrap. This stuff is excellent as it not only seals the crimped joint itself but also bonds to the insulation on either side of the joint such that the crimp simply cannot pull loose.
Lately, this is by far my favourite method for wiring loom repair. Indeed, my much modified Honda Dominator has a reworked loom which features a couple of dozen such connections and all have been 100% reliable.
I'm not sure where you'd get the micro-crimps from ... I make my own by wrapping two turns of thin copper sheet around a suitable sized drill bit or somesuch. The end result is a twin wall copper tube, about 3mm dia and 8mm long. I'm pretty sure that I have since seen them available to buy though.

In summary, micro crimps and glue-lined shrinkwrap make the best repair (in my opinion) .. unless you can replace the entire length of wire.
Also a hairdryer is a very handy tool when working on wiring harnesses.

A quick look on ebay threw up these as possible suitable crimps.
https://www.ebay.co.uk/itm/UK-TERMIN...UAAOSw8WVf2Ipg
You'd want to check the wire gauge sizes though .. and maybe cut them shorter.
Alternatively, you might be able to cut a suitable crimp section off another terminal.

you can buy crimps ready covered in glue lined shrinkwrap but these are rubbish as the crimping process destroys the shrinkwrap .. and they're too bulky anyway.

utopia · 10-03-2021, 12:47 PM

ps.

Just to be totally clear ...
The crimps that I'm talking about are really tiny.
When fitted they are about the same dia as the original insulation on the wire.
They can also be kept very short (wire strands can be enmeshed internally) as the glue lined shrinkwrap (again very small dia) ensures a secure connection.

In addition to sealing the joint and bonding the insulation sheaths together, the glue lined shrinkwrap also spreads any subsequent flexing load along the length of conductor rather than allowing it to concentrate at the joint.

spuggy · 13-03-2021, 10:07 AM

I was seriously impressed by Milspec wire when I first encountered it - and still am. Tougher than old boots, less than half the bulk, holds crimps or soldered connections extremely well and insulator doesn't retreat on soldering or heatshrinking.

It's even more obviously superior when you're joining it to the cheapest junk manufacturers think they can get away with.

From https://www.milspecwiring.com/Mil-Sp...oot_c_472.html

Quote:

Why do we offer M22759/32 over M22759/16? Simple, M22759/32 is better! M22759/16 is a cheaper wire, with thicker insulation best suited as a general usage wire. M22759/32 is a lightweight, high temperature airframe and avionics wire insulated with a single layer of cross-linked, modified ethylene-tetrafluoroethylene (ETFE) coating and rated at 150 degrees C (302 degrees F). It has a tin plated copper conductor and is rated at 600V. The dual insulation provides superior cut-through and abrasion resistance making it ideal for use in Mil-Spec, Aerospace and Motorsports applications.

Yeh, it is not cheap.

Mr Gazza · 13-03-2021, 10:30 AM

Interesting to see that the Milspec cable is tinned. That seems to be an American thing?
I first came across it when I was doing some warranty work in the USA on a Wroxham built Oyster Yacht. The skipper could not believe that we were using non-tinned cables. It's a minimum spec for marine use in the USA. We also had to adjust the freezer down to -22 instead of -18 that we tend to use here.. Two nations divided by a common language eh?

If I start from scratch again with a harness job, I will definitely be using tinned cables as it stops the Verdigris creeping down the conductors and makes for excellent soldered joints. Especially handy for the starter cable that goes to the motor pole, which suffers badly from that.

I also really like Gold connectors, which simply do not tarnish and carry far greater current than conventional connectors. No electromagnetic noise from them either, which may or may not be of any use on a motorcycle, but does indicate a good firm clean connection.

Luddite · 13-03-2021, 11:24 AM

Quote:

Originally Posted by Mr Gazza

I also really like Gold connectors, which simply do not tarnish and carry far greater current than conventional connectors.

Gold is great in that it will never corrode but it's not actually as conductive as copper. (My dad was a telephone engineer and this sort of thing was drummed into me as a youth).

If you use copper's conductivity as a base of 100, gold comes in at about 70 while, perhaps surprisingly, the most conductive metal is actually silver at 105. The problem with silver, and why it's not used, is that it tarnishes really easily, (as anyone who's been forced to polish granny's cutlery on a rainy bank holiday will know).

Mr Gazza · 13-03-2021, 12:32 PM

Quote:

Originally Posted by Luddite

If you use copper's conductivity as a base of 100, gold comes in at about 70

The thing about ordinary connectors is that from the minute you push them together they will be marching past the 70 number towards nought. Gold will just keep giving for millennia and be all that's left after the rest of the bike has turned into archaeology.
The connectors I use have a bigger cross section and contact area than the conductor itself, so I have no concerns as to their efficiency.

As a point of interest; RGM motors sell some nice repro John Bull rubber harness straps, not that dissimilar to the original Monster ones.
https://www.rgmnorton.co.uk/shop/sea...15&search.y=12

They gave me a free sample when I was last in there and I think they look rather good.

09-03-2021, 06:48 PM	#1
Tim88 Registered User Join Date: Mar 2016 Location: London Bike: M1100evo Posts: 98	Broken wires in loom I have at last tracked down the cause of an intermittent fault on my right turn indicators. I had changed bulbs and cleaned the connector many times and the problem seemed to go away, but it was just coincidence. The real problem was fatigue fractures of the wires in the loom just behind the frame head stock. I peeled back the wrapping and found that the indicator wires were fractured, that is the white/green stripe and black/yellow stripe wires. I will try and solder them and heat shrink. My bigger problem is the crack, that is just about to part, iùn one of the two yellow/blue stripe wires that form the big black cable visible in the bundle at the top. I don't know what these are and the repair will be very tricky I fear. Loom repairs are horrible and I refuse to even consider bodge up crimping solutions. Not looking forward to this job but MoT due next week so have to get on with it. Any tips?[/IMG]

10-03-2021, 10:09 AM	#7
Nasher Registered User Join Date: Jul 2014 Location: Portsmouth Bike: M900 Posts: 1,510	As mentioned, well done for finding it, locating that sort of thing isn't easy. I spent a couple of years chasing faults like this on my M900 when I first brought it, but that was mainly due to bodges by previous owners, like the cut out switch on the right hand handlebar being bypassed with the smallest gauge wire I've ever seen on a bike. Nasher. __________________ Heaven doesn't want me, and Hell is afraid I'll take over.

10-03-2021, 11:17 AM	#8
Kato Dismantled Join Date: Feb 2006 Location: East Molesey Bike: Multiple Monsters Posts: 2,222	I have a 1100evo wiring diag happy to email it to you i you PM me your mail address it is B&W but does have the wire ccd's I take the pdf to work usually where I can print out in up to A0 which makes life easier, but any decent stationer/print shop will do you large format print for a couple of quid Unable to attach here as exceeds size limit... __________________ "Political correctness is just intellectual colonialism and psychological fascism for the creation of thought crime"

13-03-2021, 10:30 AM	#13
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,807	Interesting to see that the Milspec cable is tinned. That seems to be an American thing? I first came across it when I was doing some warranty work in the USA on a Wroxham built Oyster Yacht. The skipper could not believe that we were using non-tinned cables. It's a minimum spec for marine use in the USA. We also had to adjust the freezer down to -22 instead of -18 that we tend to use here.. Two nations divided by a common language eh? If I start from scratch again with a harness job, I will definitely be using tinned cables as it stops the Verdigris creeping down the conductors and makes for excellent soldered joints. Especially handy for the starter cable that goes to the motor pole, which suffers badly from that. I also really like Gold connectors, which simply do not tarnish and carry far greater current than conventional connectors. No electromagnetic noise from them either, which may or may not be of any use on a motorcycle, but does indicate a good firm clean connection. __________________

09-03-2021, 06:58 PM	#2
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,712	There’s a (sadly B&W) wiring diagram in the back of the owners manual if that helps.

09-03-2021, 07:43 PM	#3
Luddite Registered User Join Date: Aug 2011 Location: Southampton Bike: M1100evo Posts: 2,465	Well done for tracking down the problem, Tim. I had something similar on my M900, which would cut out if you turned the bars full right lock (made town riding interesting!). The yellow/blue wires you mention are the power feed to the main beam so you've got one wire to the headlight, one to the instruments and one to the switch cluster.

09-03-2021, 07:57 PM	#4
Tim88 Registered User Join Date: Mar 2016 Location: London Bike: M1100evo Posts: 98	Luddite, Thank you for that. My symptoms were similar except that the indicator worked on left and right but not when the bars were central, I have recently been practising hand signals to alert oncoming traffic while I made a right turn, ah...those old timey skills! The info regarding the yellow/blue stripe is really useful..it also explains why these wires are contained within an extra thick black secondary insulation...because they are way higher current than the other wires...so I will be extra careful with my repair. Thanks.

10-03-2021, 08:16 AM	#5
alan s4 Registered User Join Date: Sep 2013 Location: Glasgow Bike: S4 challenge Posts: 447	Had exactly the same issue with my kill switch wire. Each time I carried out a feet up you turn (on full lock) the bike would stall much to my embarrassment.....I always imagined other bikers s******ing at my inept clutch control!

10-03-2021, 11:48 AM	#9
Tim88 Registered User Join Date: Mar 2016 Location: London Bike: M1100evo Posts: 98	Dukedesmo. I think your advice is sound regarding splicing in sections of wire so that the repairs are not at the original failure site! Every bit of flexibility is needed. Today is raining and as I have to work on the bike outside I will just investigate how far back to unwrap the loom etc. to do as you suggest. Kato, thank you for your offer. I have the little diagram that comes with the owners book (probably the most useless microscopic black and white cryptic document ever printed!). I don't think I will need the diagram just yet as I only have the broken wires to repair at the moment, but please leave your offer open just in case. I will also check if there is a chart on my computer based workshop manual for future ref. Finding these things does involve more than a bit of luck, although I am always suspicious of this particular area with all the flexing that goes on.....its enough to send you to the darkside where madness lies for a 'slow rebuild' involving carbon fibre, rear view cameras and bits of aluminium and bearings etc to try and engineer the problem away...not mentioning any names of course!

10-03-2021, 12:26 PM	#10
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,545	I second what Dukedesmo has said ... best to cut out a longer section to shift the repair to a different location. I had a similar problem on my 750. In my case it was the start button wire, making it necessary to hold the button down while turning the steering from side to side, to get it to fire up. It was a good few years ago but if memory serves, I removed and replaced the entire length of wire rather than have the stiff section that a repair inevitably causes. This is not as difficult as it sounds as long as you can lay the loom out straight .. and perhaps add a little warmth with a hairdryer. Soldering is particularly bad in this respect since it causes a rock solid stiffness at the actual repair itself but leaves the immediately adjacent section of wire with no insulation sheath and therefore with maximum flexibility ... a later breakage just waiting to happen. However most if not all proprietary crimps are crude and nasty and are probably worse than a good soldered joint. If you can get hold of any bare metal micro-crimps of the sort used in the original construction of wiring harnesses, these will make a super neat and very tiny joint which adds minimal stiffness (and minimal bulk) to the conductor. Then cover that with a short section of glue-lined shrinkwrap. This stuff is excellent as it not only seals the crimped joint itself but also bonds to the insulation on either side of the joint such that the crimp simply cannot pull loose. Lately, this is by far my favourite method for wiring loom repair. Indeed, my much modified Honda Dominator has a reworked loom which features a couple of dozen such connections and all have been 100% reliable. I'm not sure where you'd get the micro-crimps from ... I make my own by wrapping two turns of thin copper sheet around a suitable sized drill bit or somesuch. The end result is a twin wall copper tube, about 3mm dia and 8mm long. I'm pretty sure that I have since seen them available to buy though. In summary, micro crimps and glue-lined shrinkwrap make the best repair (in my opinion) .. unless you can replace the entire length of wire. Also a hairdryer is a very handy tool when working on wiring harnesses. A quick look on ebay threw up these as possible suitable crimps. https://www.ebay.co.uk/itm/UK-TERMIN...UAAOSw8WVf2Ipg You'd want to check the wire gauge sizes though .. and maybe cut them shorter. Alternatively, you might be able to cut a suitable crimp section off another terminal. you can buy crimps ready covered in glue lined shrinkwrap but these are rubbish as the crimping process destroys the shrinkwrap .. and they're too bulky anyway.

10-03-2021, 12:47 PM	#11
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,545	ps. Just to be totally clear ... The crimps that I'm talking about are really tiny. When fitted they are about the same dia as the original insulation on the wire. They can also be kept very short (wire strands can be enmeshed internally) as the glue lined shrinkwrap (again very small dia) ensures a secure connection. In addition to sealing the joint and bonding the insulation sheaths together, the glue lined shrinkwrap also spreads any subsequent flexing load along the length of conductor rather than allowing it to concentrate at the joint.