Repro Wiring Harness Experience


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shiskowd
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Repro Wiring Harness Experience

Post by shiskowd »

For my 'Z restoration project I elected to purchase a reproduction wiring harness rather that sorting through the two harnesses that I had on hand. I purchased from David Silver which appeared to be identical to other on-line vendors for about the same costs.

I'm now at the wiring stage of my project and compared the new harness with the OEM harnesses. While the reproduction is accurate in terms of wire length, wire colors and connectors, the wire gauge on the reproduction is significantly less substantial than the OEM version. The repro uses what appears to be a 'light' 18 gauge everywhere where the OEM is 16 gauge for the lighter loads and 14+ gauge for the main power conductors that run from/between the regulator, battery, key switch, ignitor, headlight, etc. Granted, if using LED lamps throughout, those loads are much reduced but the wiring too/from the regulator and battery plus ground could be 20+ amps at times when charging a depleted battery which is outside of what 16 gauge should manage.

I was going to switch out the lighter wire in the new harness in those areas but elected to clean up one of the old harnesses as it would be easier and the old harness is in pretty good condition when you strip away the tattered tape. The new harness is 120 grams lighter than the OEM, that would be 120 grams less copper. I switched out a couple of the connectors that were a bit messed up on the old harness with the new connectors - the old spades fit in nice.
2010 KTM 690 Enduro Rally, 1982 Pro-Link (resto in progress), 1979 CBX 'Z, 1975 Moto Guzzi 850T
Long Sleeping '79 CBX Restoration > viewtopic.php?f=102&t=11699

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Re: Repro Wiring Harness Experience

Post by sixofsix »

Well that is good to know. The repros I have bought in the past were virtually identical. Only the oil pressure green connector was a different shade of green. I thought I got it from CMS.. I got another one from Phil and it too was identical. These were made in Japan from the original supplier.

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Re: Repro Wiring Harness Experience

Post by divan »

Sorry to be late getting in on this. I also obtained a replacement harness for my ’79 from this vendor, a couple of years ago. I was also concerned about the wire gauges, which appeared quite small. But I know that wire insulation has come a long way since 1978, when my bike was manufactured, with new insulation materials allowing much smaller/lighter overall wire sizes. The original wires, manufactured by Sumitomo, were insulated with plain vinyl, which had to be thicker to meet JASO requirements for maximum heat tolerances, etc. Newer modified vinyl and then cross-linked insulations significantly reduced the thickness of insulation, so in short, cable became much smaller in diameter. The original Sumitomo cables were all their “AN” wire, for low voltage auto/motorcycle use. The two types used in our harnesses were 14 ga and 16 ga (Sumitomo’s coding system on the insulation was “no code” for 14 ga and code “0.85” for the 16 ga – I can still see the 16 ga “0.85” codes on some wires in my original harness).
That said, I was still skeptical. So I pulled one of the “large” wires out of its connector (the red 12v+ wire into the ignition switch, where wire gauge and amperage-handling is critical on the CBX) and opened it up. As I suspected, what I found was a wire that was quite a bit smaller in gauge than even the original 14ga one from Sumitomo. This new wire consists of 30 strands, with each strand measuring 0.14mm. The diameter of the bunched (twisted) wire I measured at 1.14mm, though probably this could be (EDITED) 1.150mm, which would make this wire closer to 17 gauge than 14 gauge. Just for reference, the original 14 ga AN wire is constructed out of 26 strands of 0.32mm wire, with a bunched bare wire diameter of 1.60mm. I didn’t check the other wires in the aftermarket harness. To be fair, one could argue that the wire run lengths on the CBX are relatively short, and smaller gauge wire on most circuits would satisfy the amperage capacity limits for those lengths, under laboratory conditions. But . . . .
Photo compares original AN ignition cable (left) with aftermarket ignition cable (right)
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Re: Repro Wiring Harness Experience

Post by divan »

Correction -- the Sumitomo wire was "AV", not "AN" -- haven't looked this up in a while.
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Re: Repro Wiring Harness Experience

Post by NobleHops »

divan wrote:
Tue Aug 23, 2022 6:23 pm
Sorry to be late getting in on this. I also obtained a replacement harness for my ’79 from this vendor, a couple of years ago. I was also concerned about the wire gauges, which appeared quite small. But I know that wire insulation has come a long way since 1978, when my bike was manufactured, with new insulation materials allowing much smaller/lighter overall wire sizes. The original wires, manufactured by Sumitomo, were insulated with plain vinyl, which had to be thicker to meet JASO requirements for maximum heat tolerances, etc. Newer modified vinyl and then cross-linked insulations significantly reduced the thickness of insulation, so in short, cable became much smaller in diameter. The original Sumitomo cables were all their “AN” wire, for low voltage auto/motorcycle use. The two types used in our harnesses were 14 ga and 16 ga (Sumitomo’s coding system on the insulation was “no code” for 14 ga and code “0.85” for the 16 ga – I can still see the 16 ga “0.85” codes on some wires in my original harness).
That said, I was still skeptical. So I pulled one of the “large” wires out of its connector (the red 12v+ wire into the ignition switch, where wire gauge and amperage-handling is critical on the CBX) and opened it up. As I suspected, what I found was a wire that was quite a bit smaller in gauge than even the original 14ga one from Sumitomo. This new wire consists of 30 strands, with each strand measuring 0.14mm. The diameter of the bunched (twisted) wire I measured at 1.14mm, though probably this could be 1.50mm, which would make this wire closer to 17 gauge than 14 gauge. Just for reference, the original 14 ga AN wire is constructed out of 26 strands of 0.32mm wire, with a bunched bare wire diameter of 1.60mm. I didn’t check the other wires in the aftermarket harness. To be fair, one could argue that the wire run lengths on the CBX are relatively short, and smaller gauge wire on most circuits would satisfy the amperage capacity limits for those lengths, under laboratory conditions. But . . . .
Photo compares original AN ignition cable (left) with aftermarket ignition cable (right)

Divan, your post kicks ass.

I acquired all of Phils stock of harnesses and switches several years back and sold what I did not use to many happy folks. And I used a half-dozen of those harnesses and many more switches on our own projects too, and thought they were excellent.

More recently I dug into a "bitsa bike" project and also bought one of the newer gen repro harnesses, and I was also disappointed. It didn't fit as well, some of the connector colors were goofy and overall it did seem flimsier. I did the same and bailed out on it, dug out the best of the used ones I had and gave it a thorough cleaning and testing, replacing a few connectors as I went. And that's what I am using.

Thank you kindly for the great detail in your post; that's great reference material.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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Re: Repro Wiring Harness Experience

Post by divan »

Hi, Nils. I never got one of Phil’s harnesses, but everything I’ve read about them says they were very well-made, up to spec. Shame they’re so hard to get now. I’ve read that he sourced the wire “from the original mfg in Japan” – that would be Sumitomo, or Hitachi, for the late models. At least up to 2018, they still listed the old AV cables for sale in bulk; but when I looked today, alas they are no more. They were good for restorers, but of course there is much better cable insulation available nowadays. That’s a good thing, since the CBX produces a LOT of atmospheric heat around that engine. One place where you almost always will find heat-damaged wire on original harness is the oil pressure switch. Not a critical spot, but a good example.
When I saw what made up that repro harness, I decided to just re-build my original harness. On mine, most of the low-amp wires were still in good shape, and replacing the terminals with new crimp-and-solder versions and a connector or two was the fix. The higher amp wires were a different story. I replaced them all with new cross-linked SXL or GXL cable (SXL is the smallest diameter, good for harness work where there isn’t a lot of heat, as this stuff is pretty stiff). But I used GXL (medium size) for the critical cables up to and around the engine, especially the unswitched red wire feeding the ignition switch and alternator, and the switched black wires out of the ign switch; and I went up a size to 12 gauge there. Same with the main ground wires and the blue +12v wire into the high beam HL.
A tip: cross-linked wire can be a bit tricky to source. A lot of the stuff sold as “auto” wire is cheaply sourced and often not at spec. The stuff sourced from China and other places can be a gauge or two off, up or down (depending on the standards where they’re made). You can identify it easily because the insulation is never marked or coded. Best to stick with suppliers who code the cables, and who list both strand size and number, and circular mils, for their cables on their web sites. If you get some of the unmarked stuff, be sure to open it up and mic the strand size, count the strands. The combo is what determines the gauge range. Ha! I’m “a bit” picky here.
Dick Sullivan

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Re: Repro Wiring Harness Experience

Post by divan »

On the subject of harnesses, another tip: The original ’79 harnesses were constructed with splices joining many of the wires in the circuits. You can trace the splice points in the wiring diagram, but not the physical type or location of the splices. For example, the black wires that supply switched +12v to all +12v points of the harness are joined together in one 4-wire splice that “lives” inside the harness in the right branch (rider’s position) sub-harness a few inches past the Y-split of the main harness that’s just in front of the coils. The black wire from the ignition switch feeds the splice, and there it splits +12v between the handle bar fuse block (looped around back through the Y-split to the fuse connector), the kill switch and starter switch (using a soldered splice at the right handle bar switch), and the regulator voltage sensor circuit, running back to the regulator coupler under the right side cover.
This is just one of the 15 physical splices buried inside the main harness, joining 53 individual wires. These are all single, unsoldered, crimped barrel splices, scattered all around the harness. Most are simple tape-wrapped 3-way splices, and generally not a problem. The only other large splice is a huge 5-way splice of all of the (green) harness ground wires. This baby lives in the main harness right next to the coils. These things have held up pretty well, I’ve found, given 40+ years of service life. But if one of them goes bad – e.g., tape wrap on harness removed or scuffed off, physical damage to the harness or splice, etc., they can be a hidden devil to someone chasing volt drop or other electrical gremlins. If rebuilding a harness, it’s not a bad idea to take a look at the splices – especially the 4-way black and the 5-way green splices. They are pretty easy to find, if the tape wrap is removed – on the two ’79 harnesses I’ve examined, the splices are separately wrapped in blue tape, underneath the black tape. Don’t know about later models – I’ve never personally worked on one. For example, my ’79 developed a small voltage drop – something I could live with, but could never eliminate. When I decided to replace/rebuild my harness a couple of years ago, I found what was probably the source of the drop. In the 4-way black splice, the 14gauge wire from the ignition switch had several strands that had broken off at the splice. On closer inspection, I saw that the crimp in the barrel splice had been poorly made on that side – one side of the barrel had been crushed into the wires, clipping the outer strands. Vibration for 30 years or so had finally cut through some of the strands. I’d take this as a rare glitch in an otherwise superb original manufacturing process; but there it was.
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Re: Repro Wiring Harness Experience

Post by NobleHops »

divan wrote:
Wed Aug 24, 2022 12:52 pm
Hi, Nils. I never got one of Phil’s harnesses, but everything I’ve read about them says they were very well-made, up to spec. Shame they’re so hard to get now. I’ve read that he sourced the wire “from the original mfg in Japan” – that would be Sumitomo, or Hitachi, for the late models. At least up to 2018, they still listed the old AV cables for sale in bulk; but when I looked today, alas they are no more. They were good for restorers, but of course there is much better cable insulation available nowadays. That’s a good thing, since the CBX produces a LOT of atmospheric heat around that engine. One place where you almost always will find heat-damaged wire on original harness is the oil pressure switch. Not a critical spot, but a good example.
When I saw what made up that repro harness, I decided to just re-build my original harness. On mine, most of the low-amp wires were still in good shape, and replacing the terminals with new crimp-and-solder versions and a connector or two was the fix. The higher amp wires were a different story. I replaced them all with new cross-linked SXL or GXL cable (SXL is the smallest diameter, good for harness work where there isn’t a lot of heat, as this stuff is pretty stiff). But I used GXL (medium size) for the critical cables up to and around the engine, especially the unswitched red wire feeding the ignition switch and alternator, and the switched black wires out of the ign switch; and I went up a size to 12 gauge there. Same with the main ground wires and the blue +12v wire into the high beam HL.
A tip: cross-linked wire can be a bit tricky to source. A lot of the stuff sold as “auto” wire is cheaply sourced and often not at spec. The stuff sourced from China and other places can be a gauge or two off, up or down (depending on the standards where they’re made). You can identify it easily because the insulation is never marked or coded. Best to stick with suppliers who code the cables, and who list both strand size and number, and circular mils, for their cables on their web sites. If you get some of the unmarked stuff, be sure to open it up and mic the strand size, count the strands. The combo is what determines the gauge range. Ha! I’m “a bit” picky here.
Another gem!
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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Re: Repro Wiring Harness Experience

Post by NobleHops »

divan wrote:
Wed Aug 24, 2022 1:01 pm
On the subject of harnesses, another tip: The original ’79 harnesses were constructed with splices joining many of the wires in the circuits. You can trace the splice points in the wiring diagram, but not the physical type or location of the splices. For example, the black wires that supply switched +12v to all +12v points of the harness are joined together in one 4-wire splice that “lives” inside the harness in the right branch (rider’s position) sub-harness a few inches past the Y-split of the main harness that’s just in front of the coils. The black wire from the ignition switch feeds the splice, and there it splits +12v between the handle bar fuse block (looped around back through the Y-split to the fuse connector), the kill switch and starter switch (using a soldered splice at the right handle bar switch), and the regulator voltage sensor circuit, running back to the regulator coupler under the right side cover.
This is just one of the 15 physical splices buried inside the main harness, joining 53 individual wires. These are all single, unsoldered, crimped barrel splices, scattered all around the harness. Most are simple tape-wrapped 3-way splices, and generally not a problem. The only other large splice is a huge 5-way splice of all of the (green) harness ground wires. This baby lives in the main harness right next to the coils. These things have held up pretty well, I’ve found, given 40+ years of service life. But if one of them goes bad – e.g., tape wrap on harness removed or scuffed off, physical damage to the harness or splice, etc., they can be a hidden devil to someone chasing volt drop or other electrical gremlins. If rebuilding a harness, it’s not a bad idea to take a look at the splices – especially the 4-way black and the 5-way green splices. They are pretty easy to find, if the tape wrap is removed – on the two ’79 harnesses I’ve examined, the splices are separately wrapped in blue tape, underneath the black tape. Don’t know about later models – I’ve never personally worked on one. For example, my ’79 developed a small voltage drop – something I could live with, but could never eliminate. When I decided to replace/rebuild my harness a couple of years ago, I found what was probably the source of the drop. In the 4-way black splice, the 14gauge wire from the ignition switch had several strands that had broken off at the splice. On closer inspection, I saw that the crimp in the barrel splice had been poorly made on that side – one side of the barrel had been crushed into the wires, clipping the outer strands. Vibration for 30 years or so had finally cut through some of the strands. I’d take this as a rare glitch in an otherwise superb original manufacturing process; but there it was.
...and another pearl of a post.

I did investigate a couple of my splices, found the same, but I'll backup your comment about scuffed electrical tape like so: ANYTIME I see electrical tape on a harness I remove it, because 99 times out of 100 there's something that needs attention beneath. Also, electrical tape is a poor substitute for PVC harness tape. PVC harness tape loves to stick to itself and doesn't leak gooey adhesive. On the other hand, PVC tape is not a suitable insulator for a bare wire.

Great stuff Dick, thanks a ton for the great content.

N.
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Re: Repro Wiring Harness Experience

Post by NobleHops »

Dick, can I probe you a little on your opinion/experience about "crimp and solder"? An experienced sage drilled it into me years ago that it was proper to do one or the other on the union of a wire and a spade/socket, but not both and the reason he was adamant about NOT soldering crimped connectors was that the solder led to strands breaking when the wire was flexed, resulting in increased resistance and heat and all the assorted badness that stems from that.

You are obviously an expert on these wiring subjects, and so I am not trying to challenge you on that, but I would be very interested in your experience and point of view on it too, so I could learn from it.

N.
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Re: Repro Wiring Harness Experience

Post by divan »

Nils -- First, thanks for the puff, but I'm by no means an "expert" on any of this. I'm just, like a lot of the rest of us, a long-time CBX'er (and some other bikes before), and an even longer-time amateur electronics diddler (ha) -- since I was a kid. Just a whole lot of curiosity that drives me to try to learn about the things I diddle with. Lots of mistakes involved in those learning processes.
I do agree with you about the tapes -- I wrap bare splices with electrical (insulating) tape -- 3M Super 33 is a great insulator, 3MSuper 88 also, for extra scuff protection (it's thicker). But PVC tape and/or tubing is as you note is tougher against abrasion and also add great heat insulation. Electrical tape alone can lead to problems.

On the soldering. Again, I'm not an expert, so here's my amateur 2 cents worth. A lot of controversy here. I've read academic papers where they lab-tested soldered vs crimped electrical joints, primarily for electrical conduction in low voltage applications (this had more to do with electronic apps than anything else), and others on twisted vs bunched wire conduction, etc etc. In the end there was no consensus on "do" or "don't do" -- just best practices in particular applications. What I gleaned from this is that properly soldered joints do increase conduction, but just a bit. In general, the main thing I've learned about it is that one solders a joint to increase strength more than conduction. But as with anything, here's the fly in the ointment.

Soldering is a learned skill, and it takes lots of practice (and failures) to get reasonably good at it. A poorly soldered joint can reduce conduction, by being either too cold or too hot, frying or hardening insulation, oxidizing the wire strands (introducing resistance at the joint) and so on. A properly soldered joint is made by knowing/using the right heat with the soldering tool (an adjustable tool is helpful, especially for novices). The heat range is related to both wire size (here all copper wire of course) and heat tolerance of the copper connector (mostly wire terminals on our bikes). For most of us, this means experimenting with the tool and the materials before tackling the actual job. As with any soldering, heat the wire and terminal to the point where the solder will flow freely (thus the experimenting) when just touched to the copper, remove the heat, flow the solder -- just a very small bit -- too much makes a poor bulky joint. The objective is to get the solder to coat -- "tin" -- the wire strands and the surface of the terminal in contact with the strands -- no more. This adds both small conduction improvement through the joint and some strength to the joint. By strength, I mean it helps prevent the wire strands from loosening in the crimp over time, something that can happen if the mechanical crimp is not quite as well made as it should be.

Solder or not solder? I'm in the middle on this (sorry -- no controversy). Properly crimped joints are, in my opinion, just as effective as soldered joints, if we're talking about the terminals on a CBX harness. If properly crimped, the wire bunch is compressed so that the strands are all in optimum contact with one another for good conduction and in good circumferential contact with the terminal itself. A properly crimped joint also will not likely see the wires loosen in the joint over time. A good example -- the original CBX harnesses. Beautiful work there, in general. We mostly have problems with poor wire maintenance -- some physical abuse too -- where the terminals corrode, introducing resistance.

The other, more prominent culprit in volt drop at terminals, is the connection between the male and female sections joining within the couplers. There, the contact points for conduction are very small surfaces between the "rolls," as they're technically called -- the little semi-round parts on the female terminals -- and the blades on the male terminals. The very thin bottom of the tips of the rolls and the flats of the blades are the primary points where conduction occurs. Those conduction points are visible as two short score marks on the blades. Over time, and with numerous disconnects, the physical orientation of the roll tips with the blades can and does loosen up, sometimes to the point where only one roll is making contact (typically), or poor maintenance leads to oxidation on the blades and rolls, reducing contact and introducing resistance, or both rolls are only minimally in contact with the blade. I've even had brand new terminals with miss-aligned rolls, so that there is poor conduction contact from the get-go.

So the bottom line, for me: I agree with your sage, with some caveats (no "rules" are ever absolute). IF you know how to properly crimp a terminal, and use a good crimping tool, no need to solder. IF you don't know much about soldering, either learn, and practice, or do not solder. If you can crimp pretty confidently and solder -- then why not? It's extra insurance. A good solder job will not degrade the joint. As for flexing the whole thing, a good solder job should never see solder running up the wire strands past the point where insulation is crimped into the retainer at the end of the terminal, and so the wire remains flexible all the way up into that point, within the insulation. A bad solder job will, yes, push too much heat up into that insulation, drawing solder with it, likely damaging it and stiffening the soldered wire inside and beyond (however far it travels). On a good job, though, with our terminals, no wire strands should ever BE exposed (out of insulation) beyond the terminal. If it is, it can be damaged, yes -- soldered or not.

The photo below is something I did for an article on switches, using an EBay junk harness for one of the illustrations. It might help visualize some of the points here.
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Re: Repro Wiring Harness Experience

Post by NobleHops »

divan wrote:
Thu Aug 25, 2022 11:12 am
Nils -- First, thanks for the puff, but I'm by no means an "expert" on any of this. I'm just, like a lot of the rest of us, a long-time CBX'er (and some other bikes before), and an even longer-time amateur electronics diddler (ha) -- since I was a kid. Just a whole lot of curiosity that drives me to try to learn about the things I diddle with. Lots of mistakes involved in those learning processes.
I do agree with you about the tapes -- I wrap bare splices with electrical (insulating) tape -- 3M Super 33 is a great insulator, 3MSuper 88 also, for extra scuff protection (it's thicker). But PVC tape and/or tubing is as you note is tougher against abrasion and also add great heat insulation. Electrical tape alone can lead to problems.

On the soldering. Again, I'm not an expert, so here's my amateur 2 cents worth. A lot of controversy here. I've read academic papers where they lab-tested soldered vs crimped electrical joints, primarily for electrical conduction in low voltage applications (this had more to do with electronic apps than anything else), and others on twisted vs bunched wire conduction, etc etc. In the end there was no consensus on "do" or "don't do" -- just best practices in particular applications. What I gleaned from this is that properly soldered joints do increase conduction, but just a bit. In general, the main thing I've learned about it is that one solders a joint to increase strength more than conduction. But as with anything, here's the fly in the ointment.

Soldering is a learned skill, and it takes lots of practice (and failures) to get reasonably good at it. A poorly soldered joint can reduce conduction, by being either too cold or too hot, frying or hardening insulation, oxidizing the wire strands (introducing resistance at the joint) and so on. A properly soldered joint is made by knowing/using the right heat with the soldering tool (an adjustable tool is helpful, especially for novices). The heat range is related to both wire size (here all copper wire of course) and heat tolerance of the copper connector (mostly wire terminals on our bikes). For most of us, this means experimenting with the tool and the materials before tackling the actual job. As with any soldering, heat the wire and terminal to the point where the solder will flow freely (thus the experimenting) when just touched to the copper, remove the heat, flow the solder -- just a very small bit -- too much makes a poor bulky joint. The objective is to get the solder to coat -- "tin" -- the wire strands and the surface of the terminal in contact with the strands -- no more. This adds both small conduction improvement through the joint and some strength to the joint. By strength, I mean it helps prevent the wire strands from loosening in the crimp over time, something that can happen if the mechanical crimp is not quite as well made as it should be.

Solder or not solder? I'm in the middle on this (sorry -- no controversy). Properly crimped joints are, in my opinion, just as effective as soldered joints, if we're talking about the terminals on a CBX harness. If properly crimped, the wire bunch is compressed so that the strands are all in optimum contact with one another for good conduction and in good circumferential contact with the terminal itself. A properly crimped joint also will not likely see the wires loosen in the joint over time. A good example -- the original CBX harnesses. Beautiful work there, in general. We mostly have problems with poor wire maintenance -- some physical abuse too -- where the terminals corrode, introducing resistance.

The other, more prominent culprit in volt drop at terminals, is the connection between the male and female sections joining within the couplers. There, the contact points for conduction are very small surfaces between the "rolls," as they're technically called -- the little semi-round parts on the female terminals -- and the blades on the male terminals. The very thin bottom of the tips of the rolls and the flats of the blades are the primary points where conduction occurs. Those conduction points are visible as two short score marks on the blades. Over time, and with numerous disconnects, the physical orientation of the roll tips with the blades can and does loosen up, sometimes to the point where only one roll is making contact (typically), or poor maintenance leads to oxidation on the blades and rolls, reducing contact and introducing resistance, or both rolls are only minimally in contact with the blade. I've even had brand new terminals with miss-aligned rolls, so that there is poor conduction contact from the get-go.

So the bottom line, for me: I agree with your sage, with some caveats (no "rules" are ever absolute). IF you know how to properly crimp a terminal, and use a good crimping tool, no need to solder. IF you don't know much about soldering, either learn, and practice, or do not solder. If you can crimp pretty confidently and solder -- then why not? It's extra insurance. A good solder job will not degrade the joint. As for flexing the whole thing, a good solder job should never see solder running up the wire strands past the point where insulation is crimped into the retainer at the end of the terminal, and so the wire remains flexible all the way up into that point, within the insulation. A bad solder job will, yes, push too much heat up into that insulation, drawing solder with it, likely damaging it and stiffening the soldered wire inside and beyond (however far it travels). On a good job, though, with our terminals, no wire strands should ever BE exposed (out of insulation) beyond the terminal. If it is, it can be damaged, yes -- soldered or not.

The photo below is something I did for an article on switches, using an EBay junk harness for one of the illustrations. It might help visualize some of the points here.
Outstanding. Thanks for taking the time and care here, Dick. I learned a ton.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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Re: Repro Wiring Harness Experience

Post by Rick Pope »

Wow. What a great write up. Thanks so much.

In another life, I play with bigger toys, which also can have electrical issues. I can tell you that Volvo trucks have no soldered terminals, only crimp, for the same reasons as described above.
Rick Pope
Either garage is too small or we have too many bikes. Or Momma's car needs to go outside.

AshishNJ
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Re: Repro Wiring Harness Experience

Post by AshishNJ »

Man! That is a load of info to chew in one bite 😀. I will be reading this post for a few days . Enjoy reading this stuff :)
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350

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sixpiny0da
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Re: Repro Wiring Harness Experience

Post by sixpiny0da »

I will mess this conversation up simply because I can't remember the details. I work at a nuke plant and was involved on a project where electrical connections were brought up. I had always thought soldering was the best way to go, but at the plant soldering isn't used so I had to specify non-soldered joints. The reasoning was vibrations can cause micro fractures or separations in the solder-to-wire interfaces leading to a loss in conductivity. Similar to a heat exchanger mystery we had where a thousandths of an inch separation kept it from working. That said, I also agree that application and skill matter as Dick said. So on anything that vibrates, I won't solder because if a nuke plant won't risk it then maybe there's a reason. True, a CBX doesn't experience long term, intense vibrations as plant equipment, but also as Dick said, a proper mechanical crimp will get the job done.

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