Topic: CB550F wiring harness question

[Scott S]

 I'm building a bike out of leftover parts.
 I have a wiring harness that I got with a '76 CB550K engine and 087A carbs....at least that's what the #'s on the engine indicate.

 I have a wiring harness that, according to Motogrid, is from a '76 or '77 CB550F

 The wiring harness has the #'s "32100-390-0001" and "74-12  K  2071" on it. I'm not 100% sure about the last two numbers in the "2071", as they're hard to read.
 

 That's too many #'s for a Honda part, but 000 or 010 shows a '76 or '77 CB550F.

 I'm using the controls from my CB500 and, so far, everything matches up. However, there are a few wires coming off the main harness that I can't identify.
 I know what the GR, LB/W and OR/W are. What are the BL/R and BL/Y wires? The black with a red stripe and black with a yellow stripe?


 I've consulted all the diagrams I have and, unless I'm just overlooking it, I don't see those wires listed.

[Scott S]

 Also, I need an ignition switch. This harness has the 550F only "flat" plug for the ignition switch.....not the commonly available square plug.

 A) Can I make the square plug work?
 B) If not, a good source for the "flat" plug CB550F switch?
 C) How/where does that style switch mount? Still down on the frame, on the down tube?

[Scott S]

 Anybody? Bueller? Bueller?

[LesterPiglet]

Black/red goes to your right handlebar light switch. Black/yellow goes to the left handlebar switch. Both are for the headlight.

[Scott S]

 What if I'm using the early style controls that don't have those wires? Every wire on my CB500 controls is already plugged into the matching receptacle on the wiring harness.

 I don't remember seeing those two wires in the headlight bucket either, but I'll double check.

 While we're at it, the light blue/white and orange/white are for the running lights on the front turn signals. Should be no problem to just use the solid color wires with aftermarket signals and leave off the running light function, right?

[Frostyboy]

I have a 550F & the Bl/R is power supply to the h/light fuse from the r/h control headlight switch when ign is on.
I can remember getting a r/h control that didn't have that switch, but they swapped it for me once I told em it was different.
Does your headlight work? If not hook it up to a power supply from the ign somewhere, but that means the headlight will be on all the time even when cranking & that might not be good.
The Bl/Y goes from the fuse to the l/h control  for hi/low beam. I think the hi/lo beam control is on the right hand control on a 500 isn't it?
2 other problems you might find is that on an F, the horn switch supplies power to the horn, not switching it to ground & the same with the start switch. It supplies power to the solenoid, not a ground circuit. I hope for your pocket's sake you don't have to replace both controls.

[Scott S]

 The early style CB500 controls are different. They have an OFF/LOW/HIGH switch. I'll get some pics in a few and double check the wiring.

[Scott S]

 OK, I looked at my online manual and I see what you're talking about now (my printed copy was too blurry to read).

 Here's the switch I have:


 It looks like all the wires do the same things....ignition, Hi/Lo beam, starter, etc. The brown/white wire goes to the gauges, I guess to turn on the lights in the tach/speedo when the light switch is turned on.

 If I get fused power to the headlight, I should be able to use the on/lo/hi switch as on the CB500, right?

[Frostyboy]

Here's some pics from 550 wiring diagram. On the 550, the r/h control is lights off/park lights/headlight on. The hi/lo & pass light control is on the left.

I also edited my previous post

[Scott S]

 Yeah, if you look at my previous posts, I ask about the 550F style "flat" ignition switch.
 That and the horn should be easy enough to figure out.

 Worse case scenario, I have another wiring harness, but this one seems to be in the best shape, of the two.

 What would be involved in getting the square style ignition switch to work? I understand that I may have to splice some wires, but if I could make it and the horn work  on ground.... Or, does that mean the solenoid is different, too?

[Frostyboy]

I'm sure the solenoid itself will be the same, but the start button will need to be altered or change it so there's power to one side of the solenoid & let your button earth the y/r wire to complete the circuit. I don't know what will happen to the clutch switch or diode function though. This is getting complicated 

[Scott S]

 Clutch switch? Diode? I don't think there IS a clutch switch in this set-up.

 I should mention....the engine is a CB500, in a 550K frame, with 500 controls and a 550F wiring harness......complicated enough?!

 I don't have a battery for this bike yet. This is all initial stuff, so far.

[Zaipai]

I am not exactly sure however I believe the clutch switch is on the left hand controls. I seem to recall one on my 550F however its not hear at the moment to check. So since you are using controls from a 500 if I remember correctly you probably wont have a switch however since your using the wiring harness from a 550F (dang it I need one of those!) the wire will be there and you can easily ignore it.

.: Scott :.

[Scott S]

 Um, you realize this thread is over a year old, right?

 I figured it out, got the bike wired and running, rode  the snot out of it for a season and sold it on eBay earlier this year.
 Thanks for the reply, though!

[Zaipai]

Um, you realize this thread is over a year old, right?

 I figured it out, got the bike wired and running, rode  the snot out of it for a season and sold it on eBay earlier this year.
 Thanks for the reply, though!

No I tend to forget to look at the thread dates..

TTYS,
.: Scott :.