Retrofitting Headlight On-Off switch to '81-'83 Model

5twins

XS650 Guru
Top Contributor
Messages
25,414
Reaction score
23,952
Points
813
Location
WNY
This is something I've been planning since I got my '83. It took some studying of the various wiring diagrams but I figured it out. I wanted to try to do this without having to run a bunch of extra wires, utilizing as much of the existing wiring as possible. All I ended up having to add was 3 small jumper wires. This is going to take several posts to explain it all so bear with me, lol.

The first big hurtle is getting headlight power up into the bucket so it can be connected to the "new" switch. On the stock bike, it doesn't go there. It runs from the headlight fuse to the headlight safety relay, then to the RLU, and finally up to the bucket. I actually want to eliminate the headlight power connection to the safety relay to get rid of the "auto-on" feature.

The '81 and later models have a clutch safety switch and relay. Since I had removed them, I was able to tap into a now unused wire in the relay plug to get the headlight power up into the bucket. It's location right next to the starter/headlight safety relay meant just a short jumper wire was required .....

qO7iCqh.jpg


The clutch relay plug has 4 wires running into it. Two are red/whites, power in and out to the solenoid. On mine, these have already been jumpered together to restore solenoid power and starter function. The other two are the "triggers" for the relay. One is a light blue from the neutral light, the other is a black/yellow from the clutch switch up on the lever. This is the one to tie into to get headlight power up into the bucket. So, a short jumper wire was made .....

Wa7OyoF.jpg


Headlight power comes into the safety relay on a red/yellow wire. That wire running into the safety relay was pulled out of the plug and the jumper wire fitted in it's place. The other end of the jumper wire connects to the black/yellow in the clutch relay plug .....

Mw5pNEG.jpg


ZM6DWaG.jpg


And here's the completed "jump". The end of the red/yellow wire removed from the safety relay has been covered with shrink wrap and tucked out of the way. All in all, a pretty easy and neat looking change .....

QK7gNI8.jpg
 
OK, so now that I have headlight power run into the headlight, let's look at my "new" switch. I used the right switch control from a '77 model. The original has just 4 wires coming out of it that fit into a 4-connector block, and that plugs into the harness inside the headlight bucket. The '77 switch has 6 wires but no connector block. All the wires are just individual bullets. So, I added a connector block to the wires that matched the originals (starter button, kill switch) so it could plug into the harness like the old switch did .....

IC16G1M.jpg


aAN4E7u.jpg


The remaining 3 separate wires are for the "new" on-off switch. The red/yellow will be power in, blue is power out to the tail light, and the blue/black is power out to the hi-lo switch. Studying a '77 wiring diagram showed what needed to be done with them .....

cGfT7ra.jpg


The red/yellow was connected to the black/yellow in the clutch switch plug, now being fed the headlight power. The blue was connected to the blue coming out of the ignition switch (more on this later). The blue/black ..... well ..... here's where it got interesting, lol. Originally, the blue/black coming out of the headlight safety relay and running to the RLU branched off on the way to power the meter lights. So, if you want those to work, you can't just run the blue/black in the headlight bucket directly to the hi-lo switch. You have to run it back to the RLU plug and tie it into the blue/black wire there. Fortunately, there are extra unused wires here now from eliminating the RLU that allow you to do this. I mentioned 3 jumper wires were needed. Here's the other two .....

1QyzgS6.jpg


In normal operation, the RLU feeds headlight power from the blue/black wire to the blue/yellow wire which runs up to the hi-lo switch. When you remove the RLU, you jumper those two together to restore the power flow to the hi-lo switch. If your low beam burns out, the RLU routes power on the blue/green wire to the hi-lo switch. With the RLU removed, that blue/green wire now goes unused. I used it to run headlight power from the bucket blue/black back to the RLU plug. I withdrew the blue/green wire from the left handlebar switch plug and replaced it with one of my jumpers. The blue/black from the "new" switch connects here. The end of the original wire was then shrink wrapped, folded over, and tucked back into the harness sleeve .....

8tEtG6M.jpg


pakKMHv.jpg


rH5eSPY.jpg


Back at the RLU plug, the two wire jumper you usually use to bypass it .....

aEJ22g6.jpg


..... gets replaced by the new 3 wire jumper I made up .....

WG6Ml89.jpg


C4cqGlQ.jpg


This ties the blue/black and blue/yellow together as before but also pumps headlight power into them from my "new" on-off switch. That power now works the meter lights and gets fed to the hi-lo switch to work the headlight. I'll admit, a bit of a convoluted path for the power, but it seemed the simplest way to make the meter lights work again.
 
Last edited:
OK, now the "more on this later" part about the blue tail light wire. Starting in '78, Yamaha tied the tail light directly into the ignition switch, you have no control over it, it comes on with the key. Now this wasn't too bad on the older models with just a single bulb tail light, you were only turning on one bulb. But these later Special models have 4 bulbs out back, all of which come on with the key. That's a much bigger draw on the battery and I wanted to do away with it. I wanted to retain the "Park" feature but didn't want all those rear lights coming on with the key in the "On" position. To do this, I had to modify the switch plate in the ignition switch. I had some extras so I modded one of those. The plate I chose actually came from an early XS400 Special. I chose it because it was easier to mod.

Inside the ignition switch, there is a rotating contact part that sits above the contact plate. Each end of this part has contacts with 3 bumps on them that form a triangle. In the "On" position, this part sits at about a 60° angle to the base of the switch where the fork lock comes out. In the "Park" position it sits perpendicular to it .....

ExwWCZY.jpg


v2VQbg8.jpg


These different positions allow the contact "bumps" to connect to different terminals on the switch plate. I've color coded them so you can see what gets connected. In the "On" position, the tail light (blue) is connected, and I don't want that .....

96ZncNy.jpg


To stop that from happening, I had to clip the blue wire going to that terminal. Note the difference in the two switch plates, where the wire bundle enters in relation to the groups of contacts. They're sort of like mirror images to one another. The wire bundle on the 650 plate enters by the two contact group, on the 400 plate it enters by the 3 contact group. To stop the tail light from working in the "On" position, you would need to clip the blue wire from the upper contact on the 650 plate, the lower one on the 400 plate. The contact cluster farther away from where the wire bundle enters is easier to disable, you simply clip the little jumper wire running to it. Here's the 400 plate modded, first just clipped then with the little jumper wire removed completely .....

vf9royP.jpg


mGWrQFw.jpg


This was easy and why I chose the XS400 plate to use. On a 650 plate, you would need to remove this connection .....

X38j4w4.jpg


And here's the finished, modded switch plate. A pigtail was added to the blue wire to feed in tail light power from the "new" on-off switch. A pigtail was added to the brown power out wire to connect my voltmeter to. I did this because where I originally connected the voltmeter had it reading several tenths of a volt lower than at the battery. Studying the wiring diagram revealed that there really is no good spot on these later models to tap a voltmeter into, except right where the power comes out of the ignition switch. Anywhere else is running through multiple splits and one of the second 10 amp fuses.

DKTUgcx.jpg
 
Oh, the "finished" install .....

Y2xslAZ.jpg


I'll also mention that in '82, Yamaha gave the right switch assembly it's own dedicated ground wire. That's what the 4th wire coming out of the original housing is, a black ground wire. It attached right to the starter button mounting screw .....

gEEWiep.jpg


bm9GPKi.jpg


With my "new" switch housing, I no longer used that and reverted back to the old "through the handlebar" ground set-up. It works just fine.
 
Call me "old school" if you like, but I just like having control over my lights, having the ability to turn them off. Up until the late '70s, all bikes had this feature, and pretty much always did ever since motor bikes came out. It didn't cause any catastrophes that I know of, and certainly wasn't a world ending feature. It was just a common sense thing - turn the lights on when needed, turn them off when you don't. Somehow the government got it into their heads that we couldn't be trusted with the great responsibility of turning our headlights on and off so they took it upon themselves to "save" us from ourselves, lol.
 
I totally agree 5T. I hate it when vehicles try to do my thinking for me (with the exception of ABS - of which I am an unshakable fan).

On cars, the thing that I detest most is the General Motors "orgasmatronic" windshield washer system which puts no fewer than 5 squirts of washer juice on the window.

No matter how gingerly you touch that washer switch, you get the full meal-deal five squirts. How stupid and wasteful. I can decide how much GD%$#@#$## windshield washer fluid I want on my f#cking windshield and I don't need some programming-safety Nazi from Warren Michigan to figure that out for me - thanks very much.

NO other OEM else does that - but GM has had that totally unwanted "feature" for a donkey's age.....answering a question that nobody asked.

Geeezzz....I am annoyed now.

I'd better go out to the DCW and play with my new toy....;)

Pete
 
I totally agree 5T. I hate it when vehicles try to do my thinking for me (with the exception of ABS - of which I am an unshakable fan).

On cars, the thing that I detest most is the General Motors "orgasmatronic" windshield washer system which puts no fewer than 5 squirts of washer juice on the window.

No matter how gingerly you touch that washer switch, you get the full meal-deal five squirts. How stupid and wasteful. I can decide how much GD%$#@#$## windshield washer fluid I want on my f#cking windshield and I don't need some programming-safety Nazi from Warren Michigan to figure that out for me - thanks very much.

NO other OEM else does that - but GM has had that totally unwanted "feature" for a donkey's age.....answering a question that nobody asked.

Geeezzz....I am annoyed now.

I'd better go out to the DCW and play with my new toy....;)

Pete

Ha, Ha, sounds like you have a bug up your a*^$%...............

Nice write up..........

Never had a drama with the 83 and headlight.............just a simple procedure to turn the key off and on again to reset the headlight if the bike didn't catch the first time................

Would still have to put my hand in front of the light to make sure it was on before riding off...........same with the on off switch, still checked with my hand to make sure the light was on...............

Don't know why you are complaining about a safety feature that has the potential to save your life...........Although cagers will always say they didn't see ya after hitting you................... if the headlight is always on it has to help save a life or 2 and just maybe yours.............
 
True about the safety issue Skull but it still is handy to be able to run dark if you are coming home late or putting through a campground.
 
I totally agree 5T. I hate it when vehicles try to do my thinking for me (with the exception of ABS - of which I am an unshakable fan).

On cars, the thing that I detest most is the General Motors "orgasmatronic" windshield washer system which puts no fewer than 5 squirts of washer juice on the window.

No matter how gingerly you touch that washer switch, you get the full meal-deal five squirts. How stupid and wasteful. I can decide how much GD%$#@#$## windshield washer fluid I want on my f#cking windshield and I don't need some programming-safety Nazi from Warren Michigan to figure that out for me - thanks very much.

NO other OEM else does that - but GM has had that totally unwanted "feature" for a donkey's age.....answering a question that nobody asked.

Geeezzz....I am annoyed now.

I'd better go out to the DCW and play with my new toy....;)

Pete
Ever driven a Toyota Avensis from around 2005 or so? Automatic windshield wiper control. Goes totally bananas in heavy rain. Absolutely horrible.
 
Call me "old school" if you like, but I just like having control over my lights, having the ability to turn them off. Up until the late '70s, all bikes had this feature, and pretty much always did ever since motor bikes came out. It didn't cause any catastrophes that I know of, and certainly wasn't a world ending feature. It was just a common sense thing - turn the lights on when needed, turn them off when you don't. Somehow the government got it into their heads that we couldn't be trusted with the great responsibility of turning our headlights on and off so they took it upon themselves to "save" us from ourselves, lol.
In most european countries, daylight driving lights are mandatory, for all road vehicles. For motorbikes, riding with lights on also in daylight has been mandatory since around 1980 in Norway. It is definitely a good thing, especially in high latitudes, due to the low sun. It is very hard to spot any vehicle with the midnight sun straight into your windscreen or faceshield.
But I still prefer manual switches for the lights on my motorbikes. My "newest" bikes are a 95 Ducati Monster and a 97 ST2. Both have manually switched lights.
So the case of Yamaha complicating things in absurdum 40 years ago, must be down to their own ideas, or perhaps caused by the lawsuit risk in the US market.
 
It's the law here too, has been for years, and I'm OK with driving with the lights on. I just don't feel the need for them at all times, like when I'm sitting in the driveway tuning my carbs or testing electrical components. Leave yours be if you're happy with it. I wasn't so I "fixed" it, lol.
 
Excellent description 5T though I'm glad that the technique you showed me for my '78 was a little easier. Yes, an automatic headlight is the Dept of Transport "request" here for all bikes I believe. When I returned mine to manual, it caused a hiccup in my Roadworthy inspection - until I plugged the blue/black back in and she functioned according to regulation. The inspector was also an XS owner, '79 I recall, and he took notes on the process for his own referral - your name is respected in the antipodes 5T.
Doug is right about the safety issue. Stats show that an unlit bike is 2 to 3 times more likely to be involved in an accident but, with the XS' notorious electric starting issues, I felt it better not to have the battery loaded with lighting up the head and tail lights while I tried to avoid having to kick the old girl. I turn it on when I ride and often forget to turn it off, (encroaching age), so it is probably on when I start it anyway - with this mod, at least I have the choice!
Cheers
 
Yes, on a '78 model, the "fix" is much easier. It was the last year to come with a headlight on-off switch in the right control assembly. But it was also the first year to come with that auto-on headlight safety relay. The handlebar on-off switch only functioned with the key on, motor not running. As soon as you started the bike, the headlight safety relay kicked in, bypassing the handlebar on-off switch and turning the headlight on. It was easy to "fix" though .....

vG1TF6W.jpg


But, this doesn't address the tail light "always on" issue. 1978 was also the first year Yamaha wired the tail light directly to the ignition switch. The headlight on-off switch doesn't control it anymore like on older models, the key does. But as I mentioned earlier, on these earlier models with only one tail light bulb, I don't consider it too much of an issue. On mine, I installed a LED tail light bulb so the battery draw is practically nothing. It can be "fixed" though if you wanted to. It would require a similar mod as above to the ignition switch plate, clipping the blue wire feed to the "On" position tail light contact and adding a blue wire pigtail to the switch plug. It's something I may do in the future, but I don't consider it a pressing matter, not like the 4 bulbs on the rear of the '83. I HAD to "fix" that, lol.
 
Yes, I believe that was the "fix" you demonstrated for me earlier. My headlight/tail light now only operates when I turn on the switch on the handlebars. If I reconnect the blue/black, it goes back to the factory setting with the headlight coming on with the ignition. Not sure if the tail light comes on as well, I will have to check. I certainly appreciate that modification.
Cheers
 
So, I have a little update to my install. Recently, there was discussion in another thread about a possible feedback issue occurring when mounting this switch on a multi-fuse Special. If you turn the key to "Park", power will feed back through the blue wire running to the headlight on-off switch. Turn the switch on and that power will continue to feed back through the R/Y wire to the fuse box. Since all the 10 amp fuses there split off the same power feed wire, they will all get powered. The bike is basically turned on and can be started and driven off even with the key removed. So I checked mine and, low and behold, I did indeed have this issue, lol.

So, the "fix" is to install a diode in the blue tail light wire coming out of the headlight on-off switch. A diode allows current flow in one direction only, and blocks it in the other direction. In this case, I want power to flow out of the switch to the tail light when I turn it on, but not back into the switch when the parking light is activated.

Ar7hRHq.jpg


The band on the diode indicates the direction the current will be allowed to flow, in my case, out of the switch.
 
Call me "old school" if you like, but I just like having control over my lights, having the ability to turn them off. Up until the late '70s, all bikes had this feature, and pretty much always did ever since motor bikes came out. It didn't cause any catastrophes that I know of, and certainly wasn't a world ending feature. It was just a common sense thing - turn the lights on when needed, turn them off when you don't. Somehow the government got it into their heads that we couldn't be trusted with the great responsibility of turning our headlights on and off so they took it upon themselves to "save" us from ourselves, lol.
While I endorse your sentiment I do find some people should not be in charge of a light switch, never mind a car.
 
Back
Top