electrical system redesign

[fatpat]

BG: If you had to do this all over again and you wanted to keep all of the stock 'accessories' would you still re-wire from scratch?

Sounds like an interesting project, but I'm not sure it's worth the pain

[beergood]

Indeed I would. Keeping all the stock accessories would only require me to run a few more wires. Over the years the original wiring was getting pretty nasty. It was covered in tape adhesive and grease and what not. It was stiff, and unpleasant to work with. The bullet connectors were for crap, and I wasn't wild about the routing of the wiring in some places.

Admittedly, it was a chunk of work. Sometimes I enjoy undertaking a large, daunting task. The wiring on my bike has always been its Achilles heal. I have been a hundred miles from home and had a bad ground appear from nowhere and require me to tear my bike half apart on the side of the road. A light rain could make my bike totally unpredictable (as if getting caught in the rain wasn't bad enough). Basically, it was always a worry in the back of my mind.

I rebuilt the original harness over the winter. I cleaned all the connections as best I could, soldered others, and there were still issues. In my business I have learned that it is really easy to lose focus and spend over five times longer 'fixing' something than starting from scratch. This just felt like one of those times.

Only time will tell how reliable my new work is, but I have a good feeling that I excised my bike's biggest demon.

[fatpat]

I cleaned all the connections as best I could, soldered others, and there were still issues. In my business I have learned that it is really easy to lose focus and spend over five times longer 'fixing' something than starting from scratch. This just felt like one of those times.

Ha... yes, I'm very familiar with this I can't tell you how many scripts I've tried to fix and realized days later I should have just started over from scratch.

What kind of splicing techniques did you end up using? In other words, what did you find as a suitable replacement for the 'double bullet' receptacle? I'm not of big fan of the self-stripping wire splices.

Cheers!

[Planecrazy]

fatpat, you read my mind. I was also going to suggest that beergood ditches those blue "quick splicers," because a lot of people (myself included) believe that they cause corrosion and contact failure in anything but the most protected environment. Your headlight bucket doesn't qualify as a well protected environment.

What I'd do instead is remove them and either use a heavier duty waterproof tap, or better yet just solder and seal them with silicone or at the very least, heat-shrink tubing. THEN you will have, in my opinion, beaten down your wiring "demons."

I'd also consider sheathing the main run of wires with corrugated plastic tubing to protect it against heat, dirt, and abrasion. Otherwise, looks like nice work!

Regards,

[bwringer]

Aaaack! Scotchlocks! Scotchlocks?

Evil! Evil! Hissssssss... make them go away.

Please tell me those execrable things are only temporary. Please.

You would seriously be better off stripping the wire with your teeth, then twisting it together with your fingers and covering the "connection" with a wad of moldy electrical tape.

Never has a less reliable and more dangerous device been invented. Remove those nasty things forthwith or find yourself accused of electrical malpractice.

[bwringer]

I'd also consider sheathing the main run of wires with corrugated plastic tubing to protect it against heat, dirt, and abrasion.

Yes. Do this, too.

I highly recommend using adhesive-lined heat shrink tubing. It's hard to find unless you have a pretty good electronics store nearby, (you can order it from McMaster-Carr: http://mcmaster.com ) but it's essential to making good waterproof electrical connections that won't corrode. A good marina might stock it, too.

If two wires need to be connected or disconnected, solder on spade connectors shielded with heat shrink tubing, connect with a dab of dielectric/anticorrosion grease, then cover the whole connection with heat shrink.

It's also very hard to find good connectors -- 99% of the ones you find in stores are the same crappy two brands. If there's a marina nearby, you might check with them for corrosion resistant connectors. You can also find good gold-plated connectors for use with high-end car stereo systems, but they're a bit expensive.

EVERYTHING on a bike is exposed to the elements -- there are no dry safe areas if you ever ride in the rain or through a puddle, so you have to treat every electrical connection as though it's going to need to work perfectly underwater for 20 years.

[fatpat]

I found this interesting splicing 'how-to'.

http://www.mmxpress.com/technical/connections.htm

Scroll to the "How to Solder" section. Nice splicing!

[t3rmin]

The bonus is this is all very "cafe" (minimalistic). Really fits with the theme of the bike. Nice work.

[beergood]

Indeed they are temporary. And they are only used on some lighting and other 'non-critical' systems. I mainly used them because they are quick and reliable enough for the areas I applied them. I am going to be doing a considerable amount of work on the bike over the winter and am looking into different junction options (possibly nautical).

A majority of my connections (and all used in ignition/charging) are soldered and shrink wrapped. There are still bullet connectors (new and shielded) on the rear light,rear brake, because I remove this from time to time. They will each be getting some sort of quick connect junction over the winter, along with the front lights.

The whole harness is inside a plastic enclosure.

[beergood]

Also, when my tach light goes out, that is a gremlin. When my bike suddenly dies at 1:00 AM in the ghetto, and I have to fix it on the shoulder of the road, well, that is what I call a demon.

[bakalorz]

If two wires need to be connected or disconnected, solder on spade connectors shielded with heat shrink tubing, connect with a dab of dielectric/anticorrosion grease, then cover the whole connection with heat shrink.

I heartily agree with everything you said except this little bit.

I used to do just what you said, thinking that this would give the best connections.

But at some point, someone told me that you don't want to solder.
You should never solder a connection that isn't mechanically supported on both sides of the joint.

The soldered wire is stiff, but where the solder ends the wire will flex, and this causes a stress concentration. You can mitigate the flex with heatshrink, but unless you use several layers, (preferably with different lengths) it will still form a stress riser.

I have had this bite me in the a** on other non-motorcycle projects, with the wire breaking right at the solder joints.

I have never had a crimped connection go bad though.

If you look at what they do in industry (or OEM automotive) they NEVER solder spade connectors to wire.
And I've never heard of the wire to connector crimp being a problem.

(our connector woes are mainly the connector to connector connection of the crappy bullet connectors, but not the crimps on the bullets themselves)

Just some food for thought, take it as you will.

Martin

[t3rmin]

I heartily agree with everything you said except this little bit.

I used to do just what you said, thinking that this would give the best connections.

But at some point, someone told me that you don't want to solder.
You should never solder a connection that isn't mechanically supported on both sides of the joint.

The soldered wire is stiff, but where the solder ends the wire will flex, and this causes a stress concentration. You can mitigate the flex with heatshrink, but unless you use several layers, (preferably with different lengths) it will still form a stress riser.

I have had this bite me in the a** on other non-motorcycle projects, with the wire breaking right at the solder joints.

I have never had a crimped connection go bad though.

If you look at what they do in industry (or OEM automotive) they NEVER solder spade connectors to wire.
And I've never heard of the wire to connector crimp being a problem.

(our connector woes are mainly the connector to connector connection of the crappy bullet connectors, but not the crimps on the bullets themselves)

Just some food for thought, take it as you will.

Martin

That makes a lot of sense to me. Good post!

[Planecrazy]

Martin,

My only observation is that at the point where the wire is crimped you STILL have a stress point very similar to the end of a soldered joint, and invariably THAT is where the wire will flex and weaken. If you think about it, it makes perfect sense -- the connector being crimped to the wire is going to be inflexible, just like the solder joint, but with a less reliable electrical connection.

I've had BOTH types of connections fail at that very point, and for that reason I still would advocate a soldered joint (with flex protection at both ends) as the best solution where you don't need to regularly disconnect the circuit. Incidentally, the reason why auto companies don't solder spade connections is that it would greatly increase the cost of assembly. If cost is no object, soldering and properly insulating/securing is still the best way to go, and I agree with your suggestion that proper flex protection in the form of either heat shrink or several layers of electrical tape will help make either connection last as long as possible.

Regards,

[CA180]

I'm all for soldering... I've seen very nice crimps done with fancy crimpers in many types of connections go bad. I havent seen many soldered joints go bad. Plus there's less resistance and better connection on a properly soldered spot.

[bakalorz]

Martin,

My only observation is that at the point where the wire is crimped you STILL have a stress point very similar to the end of a soldered joint, and invariably THAT is where the wire will flex and weaken. If you think about it, it makes perfect sense -- the connector being crimped to the wire is going to be inflexible, just like the solder joint, but with a less reliable electrical connection.

The big problem with soldering is that if you get the joint hot enough to get good wetting, you WILL get solder wicking out 1/4 to 1/2 inch in the wire. This puts the riser out in the open where the (nicely rigid) barrel of the connector can't protect it. All that can is the heatshrink, which is still fairly flexible to some degree. Also, with a properly done crimp, there is the locked in crimp, some uncrimped but rigid barrel, then the nylon cover, then just the insulation.
Meaning the bending stress is introduced over a gradually decreasing range of support. Its much harder to achieve this with a soldered connection.

Also, with soldering, you have to use the uninsulated connectors.
With crimping, you can use the insulated connectors, which have a strain relief built into the nylon

And finally there is the matter of assembler skill.
It's quite possible to make a crappy crimped connection (vise grips as a crimping tool anyone) but given reasonable tools and a little practice, good crimps are fairly easy to achieve.

Making a good solder joint isn't rocket surgery, but it takes a lot more skill than a crimp. Add the frequently cramped and unheigenic (greasy) conditons of trying to solder on a wiring harness, and getting a good joint can become a challenge for even the best.

I've had BOTH types of connections fail at that very point, and for that reason I still would advocate a soldered joint (with flex protection at both ends) as the best solution where you don't need to regularly disconnect the circuit.

I would agree with this under some conditions if you should never have to take the joint apart.

If you forsee ever possibly having to, then I think you are buying yourself more trouble than it's worth. I think its harder to do a good job redoing a solder joint that was taken apart than making a new virgin one.

Incidentally, the reason why auto companies don't solder spade connections is that it would greatly increase the cost of assembly.

I also thought this when I was originally told not to solder everything.
I was assured this is not the reason.

I forget when I was told about this, but it was from a source that I trusted.

I wonder what they do on aircraft, since reliability is more of a premium, and cost is less a driver there.

If cost is no object, soldering and properly insulating/securing is still the best way to go, and I agree with your suggestion that proper flex protection in the form of either heat shrink or several layers of electrical tape will help make either connection last as long as possible.
Regards,

Well, I guess we'll have to agree to disagree.

I think that done optimally, both methods can be used to form a connection that should outlast the bike.
But I think that for most shadetree mechanics, for most connections, most of the time; they are going to get results that are closer to optimum with crimps than solder.

Don't get me wrong, I am not against soldering.
I have a very nice digital readout temperature controlled soldering station with every tip I could get for it.
I'd like to think I am quite good at soldering.
I even plan to try to hand solder some SMDs for some projects in the near future.

But there are applications and mis-applications for everything, and based on the best information I have, the wiring harness of bikes is usually a mis-application for soldered joints.


As an aside for anyone still reading our little dweebfest of best connection making :-D

Whatever you do, don't buy el-cheapo bargain brand electrical tape.
The pennies you save will be repaid with hours of frustration and
aggravation ...
Get something decent from a reputable maker.
I personally like scotch brand "super 33" (I think ... going from memory)
It sticks better, and if you do have to take it off it doesn't leave nearly the gooey slimey mess.

The connections made by the prior owner of my bike used twisted wire, covered with dollar store electrical tape ... I still curse him.

Pitch the cheap junk ... do it now.