[illeagle]

Does anyone have any experience with this harness? It was advertised as a direct replacement for OEM, which is partially true, but there are A LOT of differences in the colors. I took note of all the OEM colors and have the manual, so I can refer to that as well, but the differences between the two harnesses really has me stumped. Unfortunately, 4into1 doesn't have a diagram for their harness. Which is disappointing to say the least. An Amazon customer asked if they had one and they referred him to the SOHC site, which I visted, but I can't find anything there except the OEM harness.

 

[TrialsRider]

No idea what you purchased, but I know enough about electricity to ask; what is it you are trying to accomplish with a 4 into 1 wiring harness?

 

[illeagle]

No idea what you purchased, but I know enough about electricity to ask; what is it you are trying to accomplish with a 4 into 1 wiring harness?

4into1 is the brand/website I purchased it from. They specialize in Vintage Honda parts. I am replacing the entire electrical system. New main harness, sub-harness & modern reg/rec unit. I had a few electrical gremlins previously & I was super tired of chasing them down, blowing fuses, etc.

Additionally, I was in a position where I had to take my bike into a shop recently and they ran into some problems, which they rigged a fix for & it was not to my satisfaction. They ran a primary wire all the way from the key cylinder plug to the starter motor, but in doing so they made it so my headlight would not work.

I would always shy away from electrical troubleshooting, but it's kind of a recurring issue for me so I'm really trying to dive in and get a really solid understanding of why problems occur, how to test & how to solve them. However, I figured with this particular bike, trying to track down issues on a wiring system that is 40 years old.... kinda figured it'd be easier to simply start fresh. I just don't get why 4into1 would manufacture an OEM replacement harness, use some same and some different colors and then not provide a wiring diagram for it. That's just... stupid.

 

[TrialsRider]

To completely rewire the motorcycle seems a bit excess.
... and yes, to sell you a replacement electric system with no schematic wiring diagrams for it is stupid, somebody is out to make a quick buck so I would send it back to the amazon.

If your plan is to keep the original alternator and replace everything else, you should start by making sure the alternator outputs are all good.
It was probably the horn that was burning out your fuses, make sure you replace it.

 

[illeagle]

It probably is a bit excessive, but the cost of both main & sub harness was around $100, and if it weren't for the stupid color changes, it would be well worth it just to not have to spend so much time tracking down electrical gremlins every few weeks.

I'm gonna spend a little bit of time today to see if I can figure it out, but if not then 4into1 will get a strongly worded email tomorrow 😂

 

[Teazer]

Trials is right that if a buyer is not provided with sufficient information to allow the part to be used, then it isn't a whole lot of use.

That said, most wiring looms come with connectors that make it fairly easy to work out what goes where, so it might be possible to make it work, but that only applies if you are 100% sure that it is the right harness for that particular year and model of bike. We expect suppliers to know what they are supplying but with old bikes, it is harder to be sure that a sample model is actually what it is purported to be. Suppliers often have to rely on whoever supplied the sample and that can cause problems of incorrect identification.

Electrical and carburation issues on old bikes are harder to fix because the pool of knowledge is rapidly disappearing. That means we have to learn how to do this stuff ourselves or find a friend to help and share the knowledge.

It would be nice if teh colors matched teh originals, but what really counts is whether it's the right harness for your year and model and if it's plug and play.

And back to your question: if it's not immediately obvious how to fit the harness, it is probably better to return it for a refund.

 

[illeagle]

Trials is right that if a buyer is not provided with sufficient information to allow the part to be used, then it isn't a whole lot of use.

That said, most wiring looms come with connectors that make it fairly easy to work out what goes where, so it might be possible to make it work, but that only applies if you are 100% sure that it is the right harness for that particular year and model of bike. We expect suppliers to know what they are supplying but with old bikes, it is harder to be sure that a sample model is actually what it is purported to be. Suppliers often have to rely on whoever supplied the sample and that can cause problems of incorrect identification.

Electrical and carburation issues on old bikes are harder to fix because the pool of knowledge is rapidly disappearing. That means we have to learn how to do this stuff ourselves or find a friend to help and share the knowledge.

It would be nice if teh colors matched teh originals, but what really counts is whether it's the right harness for your year and model and if it's plug and play.

And back to your question: if it's not immediately obvious how to fit the harness, it is probably better to return it for a refund.

That's kinda the thing that sucks is that all of the pin connectors were correct, and 75% of the wires were a match, but others were not. Some of those that were not were easy enough to figure out. For example, Honda uses Dark Green as their grounds, but this harness had Red/White. IMO, that's a stupid change, because I've NEVER come across any wiring where Red of any sort is the ground wire. But yeah, I think a return is on the table. Just sucks to have to do it

 

[TrialsRider]

Ok I went and searched it;
"Tired of tracking down electrical gremlins due to old broken wires or corroded connections?"
If it was a broken wire or corroded connection, how did they not find that problem for it to develop into a gremlin both of those problems are immediately apparent with a simple meter test and easy to resolve, resistance in a wire connection needs to be zero and there can not be any shorts to ground.
Send it back and fix the one that came on it, their replacement is not any better then the original. Replace the horn if it is still original, it's probably crusted with rust inside and that makes your direct short to ground without visible sparks or apparent heat.

If your gremlins are relating to your adding modern solid state devices to an ancient electrical system, those are not gremlins, that's hardware incompatibility.

 

[illeagle]

Ok I went and searched it;
"Tired of tracking down electrical gremlins due to old broken wires or corroded connections?"
If it was a broken wire or corroded connection, how did they not find that problem for it to develop into a gremlin both of those problems are immediately apparent with a simple meter test and easy to resolve, resistance in a wire connection needs to be zero and there can not be any shorts to ground.
Send it back and fix the one that came on it, their replacement is not any better then the original. Replace the horn if it is still original, it's probably crusted with rust inside and that makes your direct short to ground without visible sparks or apparent heat.

If your gremlins are relating to your adding modern solid state devices to an ancient electrical system, those are not gremlins, that's hardware incompatibility.

I actually just left the Post Office. I thought about it for a second & realized that I paid $100 & was still going to face the problem I was trying to avoid. No sense in buying a product that is supposed to plug in & be ready to rock, but still have to reverse engineer the whole harness just to get it to work. Not to mention that if/when I have to service it again later on I'm still going to have the confusion surrounding a bunch of mismatched colors.

You may be right about the modern reg/rec. I see a lot of people recommend them, but maybe I just need to order some of the old ones & see if that changes things.

 

[TrialsRider]

The manufacturers leveraged the characteristics of the appliances made at the time, to make it cheap. Incandescent lamps, zener diodes and lead-acid batteries are inherently tolerant to the systems they engineered them for.

Nothing past the three yellow wires coming out of the alternators dirty 3-phase A.C. output is compatible with modern appliances. From an economics standpoint you are far better off charging your lithium battery to power your low voltage devices off a wall outlet and keep the bikes original electrics original.
... except the horn that is a pos.

 

[illeagle]

The manufacturers leveraged the characteristics of the appliances made at the time, to make it cheap. Incandescent lamps, zener diodes and lead-acid batteries are inherently tolerant to the systems they engineered them for.

Nothing past the three yellow wires coming out of the alternators dirty 3-phase A.C. output is compatible with modern appliances. From an economics standpoint you are far better off charging your lithium battery to power your low voltage devices off a wall outlet and keep the bikes original electrics original.
... except the horn that is a pos.

Only thing is I'm not running a Li-Ion battery. The reg/reg I bought is compatible with Lead Acid... And I don't even have my horn hooked up lol

 

[TrialsRider]

and no LED with complete stock everything else perfect, you shouldn't be having any gremlins that can't be found and the stock diagram is good.

Meter test the battery at the terminals and then measure the voltage down stream towards everything, if you get the same voltage you have no resistance in the wire harness and that's not the problem, if you get a lower voltage you found a source of resistance.

Do the same with dedicated ground wires (except ohm instead of live volts).

 

[woodsman]

Clean all the contacts as you put it back together.

I have had a bunch of old Hondas' and the wiring harnesses were never the cause of electrical issues, if it was original.

 

[TrialsRider]

His bike has an excited field alternator, if you change nothing from stock and keep ahead of burned out lamps including the instrument lamps, everything works as planned, otherwise voltage problems will arise. It has both a stator winding plus a rotor field coil used to control power regulation to a predetermined load. Let some bulbs burn out or add some devices and it will start to affect the power regulation. Maintained as original is the key to avoid opening a can of worms. If you need the field coils repaired, best take them to a local shop that rewinds starters and alternators.
It has carbon brushes that will need attention regularly too. There's all your gremlins.

I can only imagine OEM breaker points and condensers must be near impossible to source by now.

 

[illeagle]

His bike has an excited field alternator, if you change nothing from stock and keep ahead of burned out lamps including the instrument lamps, everything works as planned, otherwise voltage problems will arise. It has both a stator winding plus a rotor field coil used to control power regulation to a predetermined load. Let some bulbs burn out or add some devices and it will start to affect the power regulation. Maintained as original is the key to avoid opening a can of worms. If you need the field coils repaired, best take them to a local shop that rewinds starters and alternators.
It has carbon brushes that will need attention regularly too. There's all your gremlins.

I can only imagine OEM breaker points and condensers must be near impossible to source by now.

Hmmm... I did make some changes to lighting and I installed a electronic ignition system. The lighting stuff I didn't think would be too much of an issue because none of it is LED or anything too fancy. Sealed beam headlight with the usual 50/60 bulb. Basically same OEM specs for taillight. The only real difference was that the turn signals were 3-wire instead of 2-wire, but I don't think the difference in any power draw would be enough to explain my issues.

I'll include links at the bottom of the post to each of the products I've changed here.

The electronic ignition... I don't think would be an issue either. In fact, the bike runs pretty good, the electrical issues are just lighting problems. Though the electronic ignition has 5 Ohm coils and I think stock ran 3 Ohm. However, I have not read anywhere that anyone has had lighting issues simply due to the electronic ignition install. I've read nothing but good things about the electronic ignition systems. In fact, I spoke to the builder at Rawhide Cycles in Boise last year and he recommended that above all else, changing to the electronic ignition system would be the top priority for any vintage Honda. He built a CB750 called Golden Goose. Look it up if you have a moment, the bike is BEAUTIFUL.


I think what I'm gonna do is get an original regulator & rectifier and see if anything changes.



Reg/Rec: Regulator / Rectifier - Lithium & Lead Acid - Honda CB350F CB400F CB500 CB550 CB750
Electronic Ignition: Electronic Ignition Kit - Dynatek - Honda CB500K CB550
Taillight: Tail Light Assy - 4 1/8 inch - Lucas - Chrome
Headlight: Headlight Assy - Side Mount - 7 inch - 12V - 60/55W H4 - Chrome
Turn indicators: Turn Signals - Rectangle - Shorty - Chrome - Amber Lens - Pkg 2

 

[TrialsRider]

Here you go, if you can read through and understand this article then you will likely be able to make everything work:
Voltage Regulator for Excited-Field Alternators

 

[TrialsRider]

OEM CB550 headlamp only draws 35/35 not 60/55 watts

 

[illeagle]

OEM CB550 headlamp only draws 35/35 not 60/55 watts

Oh? Well, the headlight has worked in the past, so not much more to say about that. The diagram... still kinda learning how to read these electrical diagrams, but I think i have it figured out. The regulator has 3 wires, Green, white, and Black. The rectifier has a 6 pin connector. The rec can obviously only get plugged into the female counterpart, so that's kinda idiot-proof.

Reg: Green is ground, black trails back to battery neg, and the white connects to the battery positive/main power in the harness. So I checked continuity last night.... the test light goes on when I check at the wire on the reg/rec, but I get nothing when I check at the rat's nest housed under the tank. So... the current is getting cut off somewhere between the sub-harness & the rat's nest. However, i don't see any visible evidence of anything that would cause that. There's no burn/melt anywhere on the harness... but I suppose it's POSSIBLE that there is some kind of failure in the wire buried in the harness?

 

[TrialsRider]

"really trying to dive in and get a really solid understanding of why problems occur"
"I had a few electrical gremlins previously & I was super tired of chasing them down, blowing fuses, etc."
"the headlight has worked in the past, so not much more to say about that."

Other then I think you probably just figured out why you were blowing fuses, you over-loaded the electrical system when you put the hotter head lamp on it. That's just like putting a 100 watt light bulb into a lamp that has Maximum 60 watts stamped on it, you're either going to fry something or start a fire.

See any copper wire that looks blackened instead of bright copper colour? That's the tell for copper wires that were over-heated, but not enough to melt the plastic connectors or outer shielding.

 

[illeagle]

"really trying to dive in and get a really solid understanding of why problems occur"
"I had a few electrical gremlins previously & I was super tired of chasing them down, blowing fuses, etc."
"the headlight has worked in the past, so not much more to say about that."

Other then I think you probably just figured out why you were blowing fuses, you over-loaded the electrical system when you put the hotter head lamp on it. That's just like putting a 100 watt light bulb into a lamp that has Maximum 60 watts stamped on it, you're either going to fry something or start a fire.

See any copper wire that looks blackened instead of bright copper colour? That's the tell for copper wires that were over-heated, but not enough to melt the plastic connectors or outer shielding.

Nope, not seeing any visible signs. Ran a few more tests a few minutes ago... unfortunately, I think the red main power wire in the harness is the culprit. Test light comes on when I connect at the various points in the middle of the bike, but I get nothing when I test at the end that connects to the 6 pin connector at the ignition switch.