Headlight Wiring

5T, I sincerely appreciate both your knowledge and your patience. Your explanation is simple, (for the electrically disadvantaged) and comprehensive. I will trace the 2nd blue and see where it goes. To test the H/light and indicator assemblies, do I need to have the entire wiring system installed, (including the charging system), or can I just connect the tail light and rear blinkers and hook up a battery to test? I ask because I don't know whether I should install everything and then test it all or "simply" test as I go.
Cheers
 
You should be able to just hook a battery up, as long as the circuits to those components are connected. If you get it right, the tail light shouldn't come on with the key as long as the headlight on-off switch is off. It should only come on when you turn the headlight on-off switch on. Same for the instrument bulbs. You won't be able to test the auto-on feature for the headlight until you can start the bike. But if you've unplugged the blue/black wire back at the headlight/starter safety relay, it shouldn't come on. This is what you're trying to accomplish here, to give yourself back total control over the bike's lighting. You're trying to stop it from coming on with the key or with the headlight safety relay once the motor starts. You want it all controlled by you with the headlight on-off switch in your right handlebar switch assembly.

The batteries in these bikes aren't very big and don't hold much reserve power. Sustained cranking with the electric start will run one down quickly. That's why I feel it's best to eliminate all the extra draws you can. There's no need to have the tail light, instrument lights, or headlight on while you're trying to start the bike. They just rob power from the battery. The '77 and older models didn't have this problem. No lights got turned on with the key and there was no auto-on headlight safety relay yet.

Don't get me wrong, I do like the later models, they are more refined. I just don't see the need for all the added safety relays and auto-on lights. Luckily the '78 model was the 1st year these started being added so it only has a couple, the auto-on headlight and the always on tail light. The clutch and sidestand safety switches and relays didn't come along until a few years later.
 
Hey Dave. Keep chipping away at it. You’ll get it. It took me weeks to get mine right. Luckily I had these guys in the forum to help me through it. I don’t think I could have pulled my restoration off without them.:bow:
 
Cheers Gator, the trick is to approach the task with the same confidence the gurus on this site have attained. I'm working on it but my guru style is more like George Harrison than 5T and the lads but hell, I've tampered with the insides of my new ignition switch and I'm becoming intimate with the SE's lighting assemblies so maybe I'm on the road to enlightenment.
Life is good here except for the poor bastards burning in New South Wales and Victoria. Worst fires I've seen or even heard of in my 64 years even on this continent of extremes. Always thought global warming would be my grandkid's problem. Not so, it appears.

Attempted to charge up the 2 batteries I've had laying around. Could get the newer one up to 12V but it quickly dropped back to 11.5V which I don't think is good enough for what I'm trying to do, (or anything else for that matter). I'll give it a fluid top up and another over-night on the 4amp charger but I think a new Yuasa maintenance free or maybe a Chrome AGM is on the shopping list for Monday. Have to check the bank before I decide. I remember when I pulled the old battery out of the bike to redo the rusted battery box - the first serious job I did on the XS. Seems like yesterday but God! It's been three years. Kinda like a good marriage I suppose - you just don't notice time slip by, (or so I'm told!!). If you were waiting to go ride the Tomewin Ranges with me you'd be pissed by now. Oh well, she'll run this year.
Need a solid battery to test the wiring I have done so turned my attention back to the headlight ears. Had a win here, as the photos show. Regards Gary, 5T and Jim, the long thread, "spread and straighten" technique worked a treat. At least when I eventually light the old girl up, I'll be seeing where I'm pointing.
 

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Bit the bullet on a couple of these things today. Addressed the persistent minor gap in the headlight mountings resulting from a bent ear. Seemed to cure it finally,(Pic1).
Took the ignition out and cut the short wire. It was black not blue but the set up was the same as 5T's photo - the black jumper wire connected to the blue at "Park". Did I ask why these people can't stick to a designated colour? (Pic 2). I had to extend the blue wire from the switch to reach the ignition connector, (Pic 3), so I used some black I had laying around. At least I'm consistent with the modern manufacturer. Hooked the extended blue from the switch to the blue in the ignition connector, (Pic 4) and put it back together, (5/6). Plugged the tail lamp and rear indicators in and installed my old battery, (11.7V). Turned on the key and flicked the lights on switch and the speedo and tacho lit up. Alright! No headlamp or indicators but the tail light came on. Actually, it stayed on after I turned the switch off but I had forgotten to disconnect the blue/black at the relay. Disconnected the wire but it's still coming on with the ignition. Hope I cut out the right wire.
OK, it's not working properly but some of it is working. I hit high beam and the blue light on the tacho lit up and then I discovered that the tail light seemed to be operating off the turn signal cancel button - the tail light comes on with the ignition switch and goes off when I depress the cancel for the indicators...... interesting. Anyway, something is working. I'll go back to check what's connected to what and the condition of the connections
 

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Fiddled with it a bit more - cleaned connections and wiggled some wires. Hooked the battery up more permanently and turned things on.
Got, headlight both turn signals, instrument lights central dash pillar light,(orange) for turn signals and high beam blue. Neutral's not connected and I still have the tail light coming on with the ignition. The indicators aren't flashing, (solid colour) but the cancel switch has stopped interfering with the tail light. The brake lights aren't functioning yet. It's all pretty weak and tenuous but it is there if I can just sort it.
So.....
Why would the tail light be coming on if the internal wire is cut and the blue/black disconnected?
Should I disconnect the canceller in the interests of safety and, importantly, convenience?
I'll order a new 2 or three point flasher unit depending on the forum's advice.
I really like any kind of progress.
 
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A weak battery will often not flash the signals so that could be that issue. The blue/black wire back at the safety relay being connected or not shouldn't affect anything. It only flows power if the bike is running.

I don't understand why the tail light is coming on with the key either. You appear to have clipped the right jumper wire on the ignition switch plate. A possibility is your new aftermarket harness isn't quite right and may have some "glitches" in it. It's happened to others. My buddy got a MikesXS harness for his '80 Special II and his headlight comes on with the key now. Granted, not a major issue for him, but not right either.
 
Tail light, gauge lights are supposed to come on with the key. That blue wire has a diode so the tail light circuit does not backfeed the headlight when the headlight switch is off.
 
Yes, on a '78 and later stock system, those lights do come on with the key, but he has clipped the jumper wire in his ignition switch so they shouldn't anymore on his.
 
Bought a new AGM Motobatt battery, (MBTX14AU) and hooked her up. Suddenly, things are really bright and confident. Ignition on still gives me the tail light but there's only the neutral and meter lights on the gauges. Headlight comes on with the switch. High and low beam work and the high beam blue comes on strong and goes off with the switch. Indicators come on strong but do not flash. A search of the forums suggested that the turn signals may not flash until the motor is running - something about load being 27 watts (x2) and the battery being too weak to drive the flasher. Ordered 2 new flasher units. Stuck with the three prong to see if I can keep the canceller - may regret it yet but they're cheap enough. Moved the front wheel over to "Lock" and ignition round to "Park". Nothing.
The two blues coming from the RH switch were actually 1 blue and 1 blue black as per the diagram - eyesight is obviously becoming an issue, my 19 y o son pointed the colours out to me along with a number of comments about getting a cane or a dog. He's out of the will.
So I have the blue/black connected to the meter light double and the other blue from the switch connected to the ignition block. Don't know if this is right but 5T suggested that they were both connected to the same power feed, so they are basically the same wire. I still have the blue wire from the right side harness with absolutely nowhere to go, (pic).
Everything is so close to right but I still can't fathom why the tail light is on with the ignition and where the blue from the right side harness connects. All suggestions, (except for sell it and buy a Moto Guzzi) given focussed consideration.
 

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As I mentioned, these aftermarket harnesses don't always match originals 100%. Check to see if that extra blue is just branching off the other blue with the multiple connections coming out of the left side harness. Test for continuity between the two. If it is, you may not even need to connect it to anything. But, you should cap it off so it doesn't short out to something inside the headlight bucket because it will have tail light/instrument light power flowing through it at times.

So now, I think I have some good news/bad news for you. Good news - I think I've figured out your tail light coming on with the key issue. Bad news - I think it's due to some bad and incorrect advice I gave you. What clued me into it was the fact that your tail light still comes on with the key but doesn't come on in the "Park" position. I think I told you to clip the wrong wire on the ignition switch plate. For reference, here's that pic of the plate again. I just assumed that how the wires were grouped together was how they were connected to one another when the key was turned on or moved to "Park". I'm thinking now I was wrong about that .....

rem7yOC.jpg


By studying another pic I have of the other side of the above plate, the side with the contacts on it, and the white plastic part with contacts that makes the connections on it, I've deduced that in the "Park" position, the red and blue at the bottom aren't connected, the red and blue at the top are. The contact plates on the white plastic part have 3 little contact "buttons" on them arranged in a triangle. This is how they fall on the switch contact plate in the "Park" position .....

1PSEQyO.jpg


In the "On" position, this is how they fall. One of the little contact plates on the white part connects the blue to the red, the other connects the red to the brown .....

ykzvyWM.jpg


So, to verify this, you'll need to test your ignition switch. Unplug it and test for continuity between the red and blue in the "On" and "Park" positions. I think you'll find it in the "On" position but not in "Park". The "fix" will be to disconnect the blue from where it is now on the switch plate and re-connect it to the contact you clipped the jumper off of. Sorry about this. Like I said, I just assumed the contacts were enabled the way they were grouped together.

On the bright side, we're learning here. I think getting rid of the tail light always on feature, and adding a headlight on-off switch on a later model, are mods many would find worthwhile and would like to do. It's a good thing that we're finally sorting out the specifics of exactly how to do it.
 
How do you guys work these things out? I get confused adjusting the toaster. No need for apologies here 5T. As I said in post #21, I genuinely appreciate your time and assistance and chasing the learning curve has been part of my life experience as a teacher so... merci beaucoup mon ami.
Now, the problem at hand presents a new and exciting challenge to the electronically retarded. Let me see if I've got this straight. On the ignition plate, I have cut out the short blue wire on the left hand side. Now I remove the blue from the bottom connection and join it to the red and brown at the top by soldering it onto the solder point where the short jumper wire was connected. This will leave the bottom solder point without a wire attached.
When I disconnect the blue from the bottom, I should be able to pull enough of it through the black sheath to reach the top solder point. If not, I'll join a piece in. Pity everything is the size of a twenty cent coin. The game is afoot, wish me luck!
 

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Yes, you've got it, move that lower blue wire up to the upper open contact, where the jumper used to be. No wire will go to that lower blue contact anymore.
 
I was helping a fellow years ago. He installed a new harness on his bike. I don't recall the year, anyway when he turned on the headlight, the headlight didn't come on but one side of the turn signals did. When he hit the turns the headlight tried to flash.
In the headlight bucket he mixed up the Chocolate wire with the brown wire. The Chocolate is a turn signal and the brown is the headlight low beam.
I tell this story because you mention your eyesight and how your son is no longer in the will.
Just be sure on your wire colors.
Leo
 
XS Leo's point has gained some relevance here. I stripped the ignition out and broke it down. Checked the continuity as 5T suggested and he was correct - had continuity in "On" but not in "Park". I removed the bottom blue wire from the ignition plate, stripped it out of the casing and replaced it with a new blue wire to reach the top solder point. Soldered it up, put a bit of calliper piston grease on the plate and re-installed. Turned the ignition on and the damn tail light lit up!

Now I was getting irritable. I checked to see if the "park" light worked and... it did, but still no brake lights. Disconnected the tail light yellow and turned the ignition on and the system worked as it should - everything was lit up from the switch only. Solid blinkers of course but I'm working on that.
Considered the situation and the penny dropped. Yellow was the brake light line. What I had been reading as the tail light was actually the rear brake light. Its switch was pulled up tight and the brake light was activating. With the double filament bulb it was impossible to tell the two lights apart so "brake" became "tail" as the brakes weren't being activated. Loosened the rear brake switch off, reconnected the yellow at the tail light and voila!! Everything functioned as it should;
  • the neutral light came on with the ignition
  • the headlight switch activated the headlight and the tail light
  • high and low beam worked and the blue light lit up on the tacho
  • indicators lit up (but don't blink)
  • turn signal warning light comes on in the central pillar
  • signals cancelled when the switch was depressed
  • tail light came on in "Park"
I hooked the little park bulb in the headlight up to the blue (brown/white), coming from the right harness and earth (green to black) but it didn't light. I'll try a few combinations.
So, after cutting the short blue from the ignition plate, the tail light may have been deactivated as I was seeing the brake light. You may have been correct right there 5T however; I had no "park" light. After re-connecting the blue to the red/brown grouping on the plate I have "park" and the tailight functioning from the switch. Pretty groovy so far. Just got to sort the headlight "park" bulb and Bob's your uncle. Will get back to you.
 
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Did some forum research and it appears my American Import '78 only operated a "park" tail light. The "park" light in the headlight was not standard. In the interests of originality, (plus the fact that I'm a lazy bastard who's had a gutful of electrics), I opted to tape the wires over and close the headlight up. So now, as the illustrations suggest, at least this part is working perfectly and, unless there's a fire in the headlight bucket tonight, I can attack the charging system. Stand by for more naive screw ups and misconceptions!
5T, if you lived here there'd be a carton of your favourite beer on your porch tomorrow or a bottle of your local anaesthetic of choice, along with a friend with a funny accent ready to assist in its consumption. Unfortunately, as you live in a relatively isolated part of my world, all I can offer is my thanks. Your advice, patience and engagement is priceless.
 

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Moving onto the charge system. First re-torqued the head. To be honest, I really only re-torqued the acorn nuts 1 to 8 and bolts 12 to 15, (pic 1). Couldn't access the bolts under the spark plugs, (9 & 10), with my torque wrench and after reading the debate xjwmx and Jim had on applying torque with extensions, (2018 Head Bolt Retorque thread), I decided it was all too hard for a boy from Oz and just tightened them down firm without stripping 'em, (pic 2). They only get 16ft/lbs anyway so if they leak, I'll tighten them down some more. The prospect of stripping the little bolt over the cam tightener was keeping me awake at night, (pic 3) so I applied the "feel" technique Gary mentioned in the same thread, to that inconsiderately located fellow - tight without stripping. Don't know if my "feel" is up to par but I do play the piano and I have been married twice! Everything has been loosened and tightened in sequence so, hopefully, it's oil tight.
With the head bolted down to my satisfaction, I replaced the points, (pic 4), coils, (yes, that coil is branded WAT YONG, hmm!), (pic5), advance springs, condensers and alternator brushes. Will post some pics when she is together.
I am awaiting a new rectifier and regulator from Oregon Motorcycle Parts. Jetmechmarty recommended them some time ago.They are well made and priced if you're trying to stick to points but, the postage to Oz,($64.00 USD) is sad. Oh well, can't take it with me.
 

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I've seen your wiring work here and it's quite good. I'm surprised you would spring for that ready-made reg/rec when you could have assembled your own for much less (VR115 automotive regulator and rectifier from the electronics world).
 
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