replacing the headlight/starter relay with something ... smaller?

[CoconutPete]

I'm not against these 2, I like the headlight relay idea and while I'm wiring it up for a capacitor, I may go back to a battery later, so the starter relay is fine too.

However .....

Before I start trying to find a home for these things in the new wiring nest ..... has anyone replaced them with more "modern" relays? Seems it would be a lot easier to deal with.

It seemed like something worth asking about .... 2 relays .. 6 wires ... there's a chance this is easy ... right?

 

[XSLeo]

The safety/headlight relay can be replaced with a 5 wire lighting relay.
The starter relay not so much. The starter draws in excess on 100 amps. So getting a smaller relay means less amps.
A lot of bikes have a smaller relay they call a starter relay but they don't carry much load they just operate a solenoid. Like on a car starter. The starter relay on the XS650 is the solenoid.
Leo

 

[CoconutPete]

Leo:

Maybe i had my parts wrong .... I for some reason thought the solenoid was nothing more and the bronze part in this pic was both the headlight and starter relay:

If that part in the pic is only the safety relay then that makes things a bit easier now doesn't it..... I can replace that whole thing with a 5-wire relay?

 

[fredintoon]

Hi Pete,
like in that old joke :- Don't go! It's a trap! There's TWO of the bastards!
Your photo shows the later model's dual safety relay. Once the alternator is charging one of them won't let the e-start work and the other one turns the headlight on.
The starter relay/solenoid is that big thing with the fat wires going to it.

 

[mrtwowheel]

I'm working on the same thing for a '74, different unit but bulky too. Think I've found a place to stuff it. I want to keep both systems.

You could cut away most of that bracket/backing plate and drill different mounting holes, zip ties could be an option.

Scott

 

[CoconutPete]

Hi Pete,
like in that old joke :- Don't go! It's a trap! There's TWO of the bastards!
Your photo shows the later model's dual safety relay. Once the alternator is charging one of them won't let the e-start work and the other one turns the headlight on.
The starter relay/solenoid is that big thing with the fat wires going to it.

Starter relay/solenoid I'm planning a location for. I'm going kick-only but building it with the fact that I may want to put a battery back in there in mind.

That leaves the starter/headlight one. I trust myself to not push the start button while she is running, but wouldn't mind the headlight functionality staying just the way it is.

Any suggestions?

Should I just keep the old copper-bastard the way it is and find a new home for it?

 

[mrtwowheel]

Any suggestions?

Should I just keep the old copper-bastard the way it is and find a new home for it?

Keep it, but put some paint on it?

Scott

 

[CoconutPete]

You could cut away most of that bracket/backing plate and drill different mounting holes, zip ties could be an option.

That entire monstrosity that is the battery "box" and the "thing" that the rectifier, regulator, starter solenoid, and said relay bolts to came out last night.

That thing is just not ... good. I'm not putting it back in the bike.

Looking for alternate ways to mount it for now. If I can find more info on replacing it later maybe I'll go that route.

 

[XSLeo]

To use a 5 terminal lighting relay isn't hard. The terminals are marked 85, 85, 30, 87A and 87.
The terminals that trip the relay are 85 and 86. The yellow wire from the alternator hooks to one, ground the other.
The terminal 30 is power in. Terminal 87A is normally on, 87 is normally off. This means that when the relay is not tripped power goes in on 30 and out on 87A. No power to 87. Wit the relay tripped power goes out on 87, no power on 87A.
Test voltage on the red/white wires. One wire runs from the kill switch, this carries power to the coil and the safety relay. After the safety relay the r/w wire runs to the light checker, TCI box and starter relay.
Well after studying the stock diagram you will need two of the relays. On one hook the r/w wire from the kill switch to 30, hook the other r/w wire to 87A
The other hook the yellow wire the same, hook the red/yellow wire to 30, hook the blue/ yellow to 87.
The r/w wires will stop the starter, the b/y and r/y turn on the headlight.
The two lighting relays will be a bit smaller but not by much.
Using just one to replace the earlier safety relay will work, on the later s/r- h/l relay I think the stock one will be easier to use.
On the 82 up that have the side stand and cut relay it might not work well.
Leo

 

[glennpm]

Take a Google look at mini relays. Panasonic/NAIS 20amp and Mitsuba RC-5001. I have about five relays of these types in my headlight bucket. The after market handlebar switches for example have very small gauge wiring. I only use these wires and all the rest of the switches as triggers for the relays.

 

[CoconutPete]

To use a 5 terminal lighting relay isn't hard. The terminals are marked 85, 85, 30, 87A and 87.
The terminals that trip the relay are 85 and 86. The yellow wire from the alternator hooks to one, ground the other.
The terminal 30 is power in. Terminal 87A is normally on, 87 is normally off. This means that when the relay is not tripped power goes in on 30 and out on 87A. No power to 87. Wit the relay tripped power goes out on 87, no power on 87A.
Test voltage on the red/white wires. One wire runs from the kill switch, this carries power to the coil and the safety relay. After the safety relay the r/w wire runs to the light checker, TCI box and starter relay.
Well after studying the stock diagram you will need two of the relays. On one hook the r/w wire from the kill switch to 30, hook the other r/w wire to 87A
The other hook the yellow wire the same, hook the red/yellow wire to 30, hook the blue/ yellow to 87.
The r/w wires will stop the starter, the b/y and r/y turn on the headlight.
The two lighting relays will be a bit smaller but not by much.
Using just one to replace the earlier safety relay will work, on the later s/r- h/l relay I think the stock one will be easier to use.
On the 82 up that have the side stand and cut relay it might not work well.
Leo

Great post!

I have decided to find a new home for the stock relay for the bike in it's current form.

Thanks!

 

[5twins]

Personally, I don't like the auto on-off headlight relay. I disabled the one on my '78 and went back to the old fashioned on-off switch on the bars. Unfortunately, your '79 eliminated that bar switch. But you could probably get it back by installing a '77 or '78 throttle housing. To disable the headlight relay, you simply unplug one wire .....

 

[CoconutPete]

5twins: Mine does not look like that. I's the "camel" version with "2 humps".

 

[5twins]

It's basically the same unit. My older version has one cover over the two relays. Your later version does not.

 

[CoconutPete]

Along with being a "2-hump version" mine also does not have a separate single wire. It's just 1 big plug w/ 6 wires.

Does leaving it unplugged prevent the starter from cranking and the headlight from lighting up I wonder.....

 

[5twins]

Leaving the relay unplugged won't stop the starter from working but it will eliminate the safety feature it's there for. The starter won't automatically disengage once the motor starts and it could be inadvertently engaged if you accidentally hit the button while the motor is running. I understand stripping a bike down and simplifying the electrics but this is a feature you need and want.

On the other hand, the headlight relay is something I don't feel is needed. In that 6 pack of wires, you should find the blue/black one. Disconnecting it doesn't stop the light relay from doing it's thing, it just stops it's relay signal from going to the lights. They won't be "told" to turn on anymore. You get to do that now with the on-off switch on the bars, just like people always did in the 50 or so years previous to this silly "improvement".

 

[fredintoon]

- - - On the other hand, the headlight relay is something I don't feel is needed. In that 6 pack of wires, you should find the blue/black one. Disconnecting it doesn't stop the light relay from doing it's thing, it just stops it's relay signal from going to the lights. They won't be "told" to turn on anymore. You get to do that now with the on-off switch on the bars, just like people always did in the 50 or so years previous to this silly "improvement".

Hi 5twins,
the "silly" thing was the "motorcycle headlight on all the time" law.
Before that, all bikes had headlight switches.
After that, bikes didn't have headlight switches and the headlight came on with the ignition.
Alas that Yamaha's e-start sucked up so much power that there wasn't enough left to run the ignition and the headlight while the starter was cranking.
Which is why Yamaha XS650 headlights don't come on with the key but only after the engine starts.
Yamaha wasn't silly, it was desperate.

 

[5twins]

That's really not true. Start cranking with your electric start and the headlight will come on even before the engine starts. As soon as the light relay senses some voltage from the alternator, it trips and the light comes on. It will stay on unless you cycle the key off and on again, even if the bike hasn't started yet. I was glad to be rid of it, lol. Now, if I can just get that tail light turned off .....

 

[CoconutPete]

Leaving the relay unplugged won't stop the starter from working but it will eliminate the safety feature it's there for. The starter won't automatically disengage once the motor starts and it could be inadvertently engaged if you accidentally hit the button while the motor is running. I understand stripping a bike down and simplifying the electrics but this is a feature you need and want.

On the other hand, the headlight relay is something I don't feel is needed. In that 6 pack of wires, you should find the blue/black one. Disconnecting it doesn't stop the light relay from doing it's thing, it just stops it's relay signal from going to the lights. They won't be "told" to turn on anymore. You get to do that now with the on-off switch on the bars, just like people always did in the 50 or so years previous to this silly "improvement".

No headlight switch on my 79'.

Also, no battery in it's current configuration, although I may decide later to add it back in.

Sounds like these things will stay put for the time being.

 

[5twins]

I know you don't have a headlight switch. They were removed from the 650 in '79. You would have to add one if you eliminated the headlight relay or the light wouldn't come on at all. It could be a simple toggle switch feeding power to the blue/black wire, or an earlier throttle assembly that has the factory switch. But you would be limited in your throttle housing choice. You would want a '76-'78 single cable assembly. Earlier ones used two throttle cables.