Topic: K1 750 wiring in headlight shell?

[ZTatZAU]

Hello all!  I've been away for a while working on other projects but I'm finally back on my bone stock 1971 (mfg 12/70) K1 750's resurrection. 

I'm presently reconnecting all the wires in the headlight shell and despite having taken quite a few pictures during disassembly as well as having the wiring diagram from the FSM and another K1 diagram from a Clymers manual, I could use some help!

Most of the connections are color coded, 1 into 1 connectors and present no problem.  There are however a couple of multiple wire connectors and I'm fairly sure I've sorted out the green ones correctly based on the pictures I took.  I am still puzzled though, on the last few remaining black wires.

I'm not sure of the correct phraseology but for clarity, I will describe the 5 harnesses that go into the rear of the headlight shell as follows:  The main harness... The left and right  handlebar switch harnesses... And the Speedo and Tach harnesses.

There are two remaining unconnected black wires coming from the main harness.  One has a single wire connector and the other has a two wire connector.  Still unconnected is a single black wire coming from the Tach harness and two black wires coming from the right handle bar switch harness.

I hesitate to assume the single black wire from the tach harness goes to the single black wire connector from the main harness... AND the two black wires from the right handlebar switch harness both go to the double black wire connector from the main harness... because... well... that would be too easy... and I don't know what the ramifications might be if I get this wrong.  Any help on this from you K1 aficionados will be greatly appreciated.

There is also one brown wire single wire connector coming from the main harness that looks like it was never connected to anything in my disassembly pictures.  Can anyone confirm that this brown wire doesn't connect to anything?

Any help or guidance is appreciated!  ZT

[BenelliSEI]

Black is power to switches and should be connected to the multi pin one from the harness. It should go live with the key on. The one to the tach feeds power to the neutral and oil lamps (the switches send the ground). The two to the right side are for power to the kill switch (feeds your coils) and power to the lamp switch. I can’t recall about the brown, will look next time in the shop. Someone else?

[ZTatZAU]

Black is power to switches and should be connected to the multi pin one from the harness. It should go live with the key on. The one to the tach feeds power to the neutral and oil lamps (the switches send the ground). The two to the right side are for power to the kill switch (feeds your coils) and power to the lamp switch. I can’t recall about the brown, will look next time in the shop. Someone else?

Thanks John!

I'm still a bit confused but it sounds like my description and assumption above was indeed correct?  That is, the single black wire from the tach goes to the single black wire connector from the main harness and the two black wires from the right handlebar harness both go to the double black wire connector from the main harness?  Is that right?

Before installing a battery in the bike and turning the key, what's the worst that can happen if I have something else connected wrong in there?  I'm thinking of the two sets of green wires... EDIT-1... two from the flashers and one from the headlight plug into the green 4-way connector from the main harness AND green from the tach and speedo to the green 3-way connector from the main harness.  Is that correct?

EDIT-2... Still wondering about the "unconnected" brown wire???

Is this as it should be?  Anyone?

ZT

[BenelliSEI]

Go for it, have a few extra 15 amp fuses on hand!

[newday777]

The Honda colors stay the same over the years.
Black is key on switched power.
The greens are ground.
Brown is taillight.
Brown/white stripe is running lights, speedometer and tach illumination.

[newday777]

The Brown wire you asked about might be for the European parking bulb in the headlight but isn't used in the US models.

[HondaMan]

The Brown wire you asked about might be for the European parking bulb in the headlight but isn't used in the US models.

That's right. They all had that Brown wire, but it was not tied to anything in the headlight bucket. This is also found in the 500/550 and the 350 twins.

[ZTatZAU]

Thanks everyone!  I appreciate your replies.

I'll proceed as proposed in my original post.
I should have a few 15A fuses around here somewhere.

ZT

[ZTatZAU]

Thanks everyone!  I appreciate your replies.

I'll proceed as proposed in my original post.
I should have a few 15A fuses around here somewhere.

ZT

Once again thanks to all who helped answer my questions.  I finished connecting the remaining black wires as proposed in my original post... turned the key on... No sparks!  No smoke!  No blown fuses.  Everything seems to be working fine... EXCEPT, the left and right flashers all come on... but they don't flash.

From what I've found searching the forum, if all flashers light up, then the wiring is correct and the problem is likely the original Signal Stat 142 flasher relay OR a bad ground.  The flashers flashed when I took everything apart a few months (?) ago so it's hard to believe the flasher relay went bad sitting on the bench.  But who knows?

I'll first check all the grounds and will appreciate any suggestions on where to start looking.  If I can't find a bad ground, I'll replace the flasher.

ZT

[CycleRanger]

Was the bike running when you tested the blinkers?
With the original flasher the battery alone might not provide enough voltage for it to work properly.
Especially if the battery is down a bit from sitting.
Either way, I'd replace replace that old can with a solid state flasher.
They use far less voltage and are more consistent than the old bi-metal flasher.

[bryanj]

If ALL the indicators come on something in the switch is weong, if just the front remember there are running lights in the front ones and twin filament bulbs, the 5 watt running lights connect to the orange with white stripe and light blue with white stripe. The indicotor 21 watt go to solid orange and solid light blue.

The switch turns off the running lights and on the indicatore

[ZTatZAU]

If ALL the indicators come on something in the switch is weong, if just the front remember there are running lights in the front ones and twin filament bulbs, the 5 watt running lights connect to the orange with white stripe and light blue with white stripe. The indicotor 21 watt go to solid orange and solid light blue.

The switch turns off the running lights and on the indicatore

Thanks for your reply Bryan, but I have confirmed what I remembered reading... that is, if the flashers light up when selected, but don't flash, then the flasher wiring is correct and the problem is likely the flasher relay.

IIRC, you are from the UK and the K1 750 flasher lights may be different there; but the K1 750s here in the US don't have running lights.  The flashers are only turn signals and don't light up unless the turn signal is selected.

With that said, I do appreciate you trying to help!

Was the bike running when you tested the blinkers?
With the original flasher the battery alone might not provide enough voltage for it to work properly.
Especially if the battery is down a bit from sitting.
Either way, I'd replace replace that old can with a solid state flasher.
They use far less voltage and are more consistent than the old bi-metal flasher.

Thanks CR!  Your advice is/was well taken.  The engine is not yet running so I was testing with a well charged (12.6v) battery.  Even so, I hooked up a 1.5A trickle charger (13.1+ V) and tested again with the same results... I.E. Turn signals came on but did not flash.

So I went to the local autoparts store and picked up a cheap $5.99 round two prong 12V flasher and plugged that in to test with only battery power, and... Voila!  My turn signals are now flashing again!

I'm not crazy about the cheapo flasher 1) because it doesn't fit in the rubber "suspension" mount and 2) the cheapo flasher's case does not look like it's intended for "exterior use".  The backside looks like coated cardboard that's crimped onto the back of the can.  It should however do in a pinch... at least for a while.

It so happens that I restored a 1973 XLH 1000 a couple years ago and it seems to go through flasher relays in a season or less.  I just ordered 3 flashers for the XLH to have on hand and if I'm not mistaken the function and size format of the XLH flasher is the same as the OEM Signal-Stat 142 flasher that came on my K1 750.  These flashers are readily available and DK, JPC, etc. for 8-12 dollars and should work fine on the 750 and may even fit in the stock rubber flasher holder.

Thanks once again to everyone who helped.  My next steps are to install new badges and bottom trim on my new Yamiya Ruby Red gas tank and modify & install my new Busso 4 into 4 No-Stamp exhaust, before getting this K1 back on the road.

I'll keep you all posted with further updates and/or more questions.
ZT

[BenelliSEI]

Well done!

[ZTatZAU]

Well done!

Thanks John!
I don't mind saying, you've been a great help on many phases of my K1's resurrection.
And I'm finally starting to feel like I'm getting close to posting some pix of my SOHC4, out on the road!
ZT

[bryanj]

Sorry didnt read your post well enough to see its a K1, in fact UK had about 30 K1 then everything else was K2 until we got the K6.
I was remembering the US imorts to UK i have worked on, the late 500 and 550 worked the same

[BenelliSEI]

Well done!

Thanks John!
I don't mind saying, you've been a great help on many phases of my K1's resurrection.
And I'm finally starting to feel like I'm getting close to posting some pix of my SOHC4, out on the road!
ZT

My pleasure! Look forward to seeing another K1 back on the road. Keep at it!

[MauiK3]

Yes, we'd all love to see the K1.
Any photos to post?

[CycleRanger]

Glad the new flasher worked, I kind of thought it would.
Used an EP35 flasher in my K5, but it's got three wires.
(I installed LED's in the blinkers as well.)

[ZTatZAU]

...
It so happens that I restored a 1973 XLH 1000 a couple years ago and it seems to go through flasher relays in a season or less.  I just ordered 3 flashers for the XLH to have on hand and if I'm not mistaken the function and size format of the XLH flasher is the same as the OEM Signal-Stat 142 flasher that came on my K1 750.  These flashers are readily available and DK, JPC, etc. for 8-12 dollars and should work fine on the 750 and may even fit in the stock rubber flasher holder.
...

Just an update, and this may be old news to some... but 12v Harley rectangular flasher relays... (p/n 68543-64A)... are indeed the same size, form, and function as the original Signal-Stat 142 flashers used on CB750 K1 through K?.  They worked great in my 750 and fit perfectly in the OEM rubber "suspension" flasher holder.

I was encouraged when, I think it was Stu (?) who posted the OEM Honda flashers were still available from Honda; but the joy evaporated when my Honda dealer confirmed a superseded p/n flasher relay was available for $47 but could not confirm the superseded flasher was the same size and shape of the original.  He also advised the rectangular rubber holder was no longer available.

So if your interested in staying fairly close to original, on a 750 flasher relay, check out the harley flasher p/n mentioned above.  They are readily available and relatively cheap... $8-$12... online or at DK, JPC, etc.

ZT

[BenelliSEI]

Good info. Thanks.

[newday777]

Cool!
Niche has them for $ 7.85

http://www.nichecycle.com/ncs/categories/electronics/flasher-relay/66-86772-flasher-12v-68543-64a-by-emgo.html

[Kevin D]

ZT,
 Sorry I’m getting here late. I posted this about a year ago when I was having trouble with the flash rate on my K1:

       

My 71 cb750 k1 has a Signal Stat 142. Sorry I can’t remember if it’s original, but likely it is.
Recently I learned a lesson about a simple thing with turn signal bulbs this: you need the correct bulbs. A 1073 bulb and its 23 watts is not an 1156 bulb with its 27 watts, and two 1073 bulbs will not flash a signal stat 142 flasher. A 1073 + 1156 will give a very slow flash. Two 1156’s have a proper flash rate.

 I bought a kit of replica signals from DSS recently when I fitted a luggage rack. They look nice and are fitted with 1073 bulbs. My K1 Honda books call for 1156 bulbs and after I weeded out the 1073’s all was well. I have had other turn signal troubles with rust, water entry, loose grounds.
 In the distant past I wired many new Hondas of all varieties out of the crate, all successfully.
An extra wire in the shell with a female connector was OK.
An extra wire in the shell with a male connector was a problem needing a remedy.
 These days it’s the faded colors (or my faltering eyesight?) that give me the most trouble.
I’m glad you got your troubles sorted ZT.

[ZTatZAU]

Thanks for the nice replies.

I've gotten a lot of help here on SOHC4 and I'm happy to help others when I can!

ZT