Topic: Should I replace these electrical connectors? '76 CB550K

[denward17]

I haven't tried to move these or check for connectivity, but should I go ahead and replace these? They look like they are crumbling in place.

Can I get just the connectors? or am I looking at a wire harness?

[Mark1976]

   Just my 2 cents here, so short answer is yes, but it'll do for the time being... I don't know about availability other than replacing with a similar aftermarket type of connector.

[bryanj]

Centre fuse is wrong length and those fuse boxes are notorious for the connector bits getting hot and loosing tension.
There is a post on here about a fuse box lid which gives a link to a replacement fuse box that fits like original OR contact Hondaman who does a plug and play replacement with blade fuses.
Either way they just plug into the main loom at a block connector

[calj737]

Replace the connectors and do any needed clean up. Here’s a good source for replacement connectors: http://oregonmotorcycleparts.com/connectors.html

[grcamna2]

The plastic female multi-wire connectors that're disappearing need replaced;what condition are the ones behind them that plug into the back side. ?  if the rear ones are ok,that'll help.
Do you have a part# tag still on the harness ?  I may have a good,used harness.

I have a decent,used harness with good plugs for a 77/78' CB550K #32100-404-670 which needs some tape on a 2" spot and a bit of cleaning if interested.
I'm not certain whether it will be adaptable to your 76' 550K,but if so,ok.

I also have the electrical panel behind it with good plugs,voltage regulator and solenoid.

[Deltarider]

Relax, mine are as old as yours and still work fine. If you have an issue, the V-4 measurement is the first step. Don't fix what ain't broken is my motto and I am not looking for chores. Just pay attention to good fuse contacts. That's the only thing sofar*, I had to do: inspect the fusebox for corrosion and clean fuse ends and clamps. When in doubt, a V-drop measurement will tell it all.
* I had to renew my IGN key switch, but that was caused by me mishandling it.

[denward17]

Replace the connectors and do any needed clean up. Here’s a good source for replacement connectors: http://oregonmotorcycleparts.com/connectors.html

Thanks for the tip, will look into these.

[denward17]

The plastic female multi-wire connectors that're disappearing need replaced;what condition are the ones behind them that plug into the back side. ?  if the rear ones are ok,that'll help.
Do you have a part# tag still on the harness ?  I may have a good,used harness.

I have a decent,used harness with good plugs for a 77/78' CB550K #32100-404-670 which needs some tape on a 2" spot and a bit of cleaning if interested.
I'm not certain whether it will be adaptable to your 76' 550K,but if so,ok.

I also have the electrical panel behind it with good plugs,voltage regulator and solenoid.

Appreciate that, but it is a different part #, so assume it is different.

[denward17]

Centre fuse is wrong length and those fuse boxes are notorious for the connector bits getting hot and loosing tension.
There is a post on here about a fuse box lid which gives a link to a replacement fuse box that fits like original OR contact Hondaman who does a plug and play replacement with blade fuses.
Either way they just plug into the main loom at a block connector

Yes, had already thought of Marks' fuse box replacement, got one from him for the 750 a while back.

[Flyin900]

Replace the connectors and do any needed clean up. Here’s a good source for replacement connectors: http://oregonmotorcycleparts.com/connectors.html

Thanks for the tip, will look into these.

Personally I would definitely replace them as vibration may cause the plastic to break in between the sections and short out. The good news if Oregon has the correct sizes, you only need the tiny tool to release the ones that don't fall out of the crumbling connectors. Then clean the brass connectors on the wire ends and push them into the brand new connector blocks. I think Oregon sells the release tool, or a tiny jewelers screwdriver can also work in a pinch.

If you look at the brass connectors he sells with the blocks they have a tiny raised metal tab as shown in the pictures. You reach into the front of the plastic connector block and depress that brass tab then pull the wire and brass connector out of the rear of the block. In your case most of those plastic block connectors may just fall apart as you try to remove the wire and brass connector. There should be no need to recrimp new brass connectors onto the wiring, just clean up the old brass connectors and insert them into the new plastic blocks.

[CycleRanger]

Oh heck yes replace them. They don't cost much and and they're pretty simple to swap out.
You can clean all the contacts and save yourself potential electrical issues down the road.

[Deltarider]

You must be looking for work. Nothing in your text nor picture suggests there's an issue. Mine look the same. The fuse box needs attention though: 1) fuses ends, 2) the clamps they sit in and 3) possibly the back of the fuse box. All these can be brought to new with little effort. For the rest, do a V-drop test first. It's what I do at the beginning of every season. Diagnosis always comes first imo.

[calj737]

You must be looking for work. Nothing in your text nor picture suggests there's an issue.

If you don’t think his connectors (cracked, chipped and exposing the spade connectors which are also oxidized) don’t warrant replacement, then I shudder to think to think what your bike looks like. 

[Deltarider]

Aah... Calj, the Old Faithful. FYI, those spade connectors are always exposed. It's the contacting part that matters. If there's resistance, a V-drop measurement will tell. The V-drop measurement I do at the beginning of the season? I can limit it to:
step 1) Batt+ - any black wire in or near the headlamp bucket. If I detect too much V-drop in that route, then and only then, I move to the next steps:
2) Batt+ - fuseholder back side
3) fuseholder back side - fuse front side
4) fuse front side - IGN key switch
5) IGN key switch - any black wire.
If everything works like horn, blinkers, lights, etc, there's nothing to worry about. If anything does not work or dimmed: check for good ground. That's it.
Replace just everything? You will have learned nothing whilst doing hours and hours of work.
Diagnosis comes first. Always.

[calj737]

Ahh, Delta- Faithful Old Garp. Constant blather. You must be a terribly lonely person to lecture others about how YOU think the world should be. Go ride your bike.

[bryanj]

For the cost of a Hondaman replacement it is simply not worth the diagnosis time plus you can then use blade fuses which are now easier to get than the correct length glass fuses as shown by the overlong middle fuse in the picture

[MauiK3]

I bought Honduran's fuse setup, works great.
I also bought a set of vintage connectors in a kit. They are very easy to assemble.
I also bought a new harness anyway, mine was very stiff, especially up at the steering neck.

[denward17]

Well, when I unplugged them, some parts of the connector broke off in my fingers, so yeah, will be replacing.

Hondaman's fuse block ordered as well.

[Deltarider]

Just as I expected, contacts in the pic look good. Sorry you damaged it by unplugging it. That's sofar the only problem I heard of, people had with them connectors: the plastic. Out of curiosity I once have unplugged one and I was amazed contacts were still that good. My other one has not been unplugged ever.

For the cost of a Hondaman replacement it is simply not worth the diagnosis time plus you can then use blade fuses which are now easier to get than the correct length glass fuses as shown by the overlong middle fuse in the picture

The cleaning of the back side of my OEM fusebox took 3 minutes. The three fuses and their clamps even less. Personally I cannot say goodbye to these OEM parts. I like too much the original modest look of it and how nicely Honda has added that grommet with 3 spare fuses fitted on the inside of the cover. Lovely detailed (see pics). BTW, I never had a 5A or a 7A fuse blow (they're both 47 years old), the 15A however a couple of them. Five 15A glass fuses for € 1,80. I can't help it, I like them. The same with breakerpoints.
The checking at the beginning of every season is done within a minute, because normally everything is fine.
When there is an issue, it's usually the fuse box (just have a quick look at it every year) or the IGN key switch. I had to replace mine, but I have to admit, I had mishandled it myself  by spraying WD-40 in it which had turned the plastic inside in some sort of goo that had gotten in between the contacts. It was typically a case of what I call overnursing. I've learned that the IGN key switch does not need 'maintenance'. I can recommend the cheap alternative from CMSNL Works perfect.
It always strikes me how often the forum is concerned with the electrics. Compared to the Italian bikes of that era (Guzzi, Laverda, Ducati), Honda electrics were dead reliable. It's almost as if members here want to play with it anyway. Crazy gadgets... relays being fitted... I did a test with a relay in the ignition supply. I cannot speak of much improvement, if any. There's -  maybe - a slight advantage at idle. And at higher than idle, in other words: riding? Not that I have noticed.

[Little_Phil]

Nothing wrong with disconnecting connectors to inspect. If they crumble they need replacing.
A relay on the ignition cuts out about five connectors an old fuse box, an ignition switch, the handlebar stop switch and a long length of wiring. Still need a fuse in the line to the relay, but it has given a voltage boost at the coils and definitely improved starting. Recommended!

[rotortiller]

It's almost as if members here want to play with it anyway.

You hit the nail squarely on the head, I bet you'd sooner buy tires and fuel lol!

[Deltarider]

Nothing wrong with disconnecting connectors to inspect. If they crumble they need replacing.

There's something wrong with being desperately longing for 'maintenance' and then start messing with things which were better left alone. The number one issue in this forum is... itchy hands.

A relay on the ignition cuts out about five connectors an old fuse box, an ignition switch, the handlebar stop switch and a long length of wiring. Still need a fuse in the line to the relay, but it has given a voltage boost at the coils and definitely improved starting. Recommended!

Wow! Stupid Honda! How could they have missed this?!
In the 70s the performance of Honda's starting was unmatched. When the CB750 was presented on a motorshow in Holland, the Honda importer made it to the TV news, when he demonstrated that just a quick touch of the starter button was enough to bring the 750 alive. He did this right after he had demonstrated how many times he had to step on the kickpedal of a BMW boxer to start that one.
 World on wheels was a well known Dutch television program about cars. In each episode they tested a car. That test always included the socalled 'cold start'. It was performed after that particular car had spent a night in cold storage. As said that program was about cars. I remember one exception. You've guessed it: they could not possibly have ignored the arrival of the CB750. As expected the bike started rightaway after it had spent a night in the deep freeze. Now, I don't know what 'boost' your bike needs, but mine can do without. The general rule of thumb in that era was, if your Made in Japan (!) bike does not start within 7 seconds, there's something wrong. And in case battery voltage would be low for whatever reason, there was always the kickstarter as back up.
The experiment I did, was even without a relay. Let me explain this. For convenience I have a wire attached to where the battery cable connects to the starter relay. In my situation it's easier to connect a charger there. I don't have to remove a side panel. I made it there because the RH (battery) side is too close to the garage wall. Now I only have to connect the POS wire from my charger to that little female connector that you can hardly see dangling just below the LH side panel (see pic). The NEG cable from the charger is connected to the foot peg. Last summer I realised that that same charge wire could be used in an experiment, for a direct line from Batt+ to the IGN POS. I only had to remember that for the duration of the experiment that wire would be live, regardless whether the ignition was switched on or off. Since this was only a test, the risk of forgetting this, was acceptable. If I would find convincing results, I could later fit one of the relays I have lying around.
Glad I did not fit one rightaway. The result was thus, that I concluded I could save myself the trouble. As said, I've seen maybe a slight improvement at idle, but when riding there wasn't any. None whatsoever.

[denward17]

There's something wrong with being desperately longing for 'maintenance' and then start messing with things which were better left alone. The number one issue in this forum is... itchy hands.

Can agree up to a certain point, but when I see something that is obviously going to give me a problem later, why not address it when I'm going head to toe through the bike?  I certainly don't want to be 25 miles from home on this bike and a connector fails (not saying a new one wouldn't), but trying to reduce the odds.

[BenelliSEI]

Nothing wrong with disconnecting connectors to inspect. If they crumble they need replacing.

+1 to the above. Ignore the BS flying about and enjoy your project.

[MauiK3]

In my case, my connectors looked pretty toasty and the wire was pretty stiff, I wanted to be more confident in the wiring so I changed the harness.