What is the best wiring diagram for a 1979 xs650 special?

Pull the Bullet connectors that go to the taillight , out of that conglomeration.........

DG, (dark Green), Right turn signal............
Ch, (chocolate), left turn signal................
L, (blue and Y, (yellow) and B, (Black) to the taillight

Q: what has he got connected to the L and Y wires
Thank you for the quick reply! I believe they are connected to just the tail light. I switched the brake light fuse today and it works fine
 
Ricky, the flasher circuit is basically fairly simple. Yamaha did their best to make it more complicated by adding self-cancel and hooking that up to the speedo to give a way to measure distance. But you don't need any of that complexity if you're willing to accept the onerous task of turning the signals off yourself. I think your PO wired the signals himself so he has probably omitted the self cancel?

The flasher unit, under the tank, is always live when the bike is switched on - brown wire from the fuse box to the flasher unit. This live signal is then carried to the flasher switch on the left handlebar. Which is isolated when the signals are off.

Selecting L or R completes the circuit so brown or green wire to left or right turn signals is now live. For each turn signal light, use your multimeter to check this wire is live when the signal is selected. If not, there is a problem between the flasher switch and the turn signal. The black wire completes the circuit from the signal back to the frame and the signal will not light unless this makes a good ground.

This simple set up is easy to follow on the circuit diagram for my bike at posting #2.
 
Ricky, the flasher circuit is basically fairly simple. Yamaha did their best to make it more complicated by adding self-cancel and hooking that up to the speedo to give a way to measure distance. But you don't need any of that complexity if you're willing to accept the onerous task of turning the signals off yourself. I think your PO wired the signals himself so he has probably omitted the self cancel?

The flasher unit, under the tank, is always live when the bike is switched on - brown wire from the fuse box to the flasher unit. This live signal is then carried to the flasher switch on the left handlebar. Which is isolated when the signals are off.

Selecting L or R completes the circuit so brown or green wire to left or right turn signals is now live. For each turn signal light, use your multimeter to check this wire is live when the signal is selected. If not, there is a problem between the flasher switch and the turn signal. The black wire completes the circuit from the signal back to the frame and the signal will not light unless this makes a good ground.

This simple set up is easy to follow on the circuit diagram for my bike at posting #2.
Now I'm starting to understand! When I test the L and R signals between the flasher switch do i pull them from the switch? As in open up the flasher unit on the handlebar to test? This may be a dumb question. Also would I do it with the bike off or on? Since its only live when the bike is on
 
Ricky, the flasher circuit is basically fairly simple. Yamaha did their best to make it more complicated by adding self-cancel and hooking that up to the speedo to give a way to measure distance. But you don't need any of that complexity if you're willing to accept the onerous task of turning the signals off yourself. I think your PO wired the signals himself so he has probably omitted the self cancel?

The flasher unit, under the tank, is always live when the bike is switched on - brown wire from the fuse box to the flasher unit. This live signal is then carried to the flasher switch on the left handlebar. Which is isolated when the signals are off.

Selecting L or R completes the circuit so brown or green wire to left or right turn signals is now live. For each turn signal light, use your multimeter to check this wire is live when the signal is selected. If not, there is a problem between the flasher switch and the turn signal. The black wire completes the circuit from the signal back to the frame and the signal will not light unless this makes a good ground.

This simple set up is easy to follow on the circuit diagram for my bike at posting #2.
Raymond your diagram is very helpful. I went back to check it out. I guess I've been confused about what the black wires with the bars under them were this whole time. Those are the ground wires? When you say they have to be grounded to the frame exactly does that mean? I think that's what I've been missing.
 
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My concern is if he has the tiallight connected to the Indicator wires.........how is that wired into the bar switches.......
 
Well, to correct what I said about the signal flasher unit - handlebar switch being live, it is only intermittently live. Coz that's in the nature of flasher units. So is the signal to each signal light. So with bike on, select L or R and use your multimeter - you could set it to Volts, 0 to 20 range and look for about 12.5 V reaching each signal.

Or, use your multimeter set to ohms Ω and check for continuity between the wire at the handlebar switch and the signal light. Resistance should be very low or there's a problem en route. You can do this with the bike turned off. Likewise, check continuity on the black earth wires. These complete the circuit, via the frame, back to the battery.
 
For example, check a black earth wire by testing resistance between the wire and the battery -ve post or the point on the frame where the -ve battery cable is earthed/grounded.
 
This is a 78SE loom i put on my 80SG...Points model.

Your headlight bucket wont look like this as you have no Gauge lights or headlight/neutral light warning lights in the rev-counter.........

May help for you to identify the loom wires that go into the bucket from the main loom and to trace some of the wires to transfer to the diagram
b DSCF7015 2 - Copy copy.jpg
 
For example, check a black earth wire by testing resistance between the wire and the battery -ve post or the point on the frame where the -ve battery cable is earthed/grounded.
When I ground a connection, such as the flashers L and R connections, does that mean the black(ground) wire has to be literally attached to the frame when you say "ground it to the frame"? I've never quite understood that
 
650Skull said:
DG, (dark Green), Right turn signal............
Ch, (chocolate), left turn signal................
L, (blue and Y, (yellow) and B, (Black) to the taillight

Q: what has he got connected to the L and Y wires

Thank you for the quick reply! I believe they are connected to just the tail light. I switched the brake light fuse today and it works fine

Going by this pic...........it looks like the indicator wires are used for the taillight??????
20201014_212503-jpg.177188
 
Power flows from the +ve Red battery terminal to the flasher unit and everything else that needs power, then back to the battery -ve Black terminal. This could be done by having a black wire from every component back to the -ve terminal. But automotive practice is to use the frame/chassis as a shortcut for those return wires. So there needs to be a good connection from each component to the frame and from the frame to battery -ve.
 
This is a 78SE loom i put on my 80SG...Points model.

Your headlight bucket wont look like this as you have no Gauge lights or headlight/neutral light warning lights in the rev-counter.........

May help for you to identify the loom wires that go into the bucket from the main loom and to trace some of the wires to transfer to the diagram
View attachment 177199
THIS IS SO HELPFUL.

My apologies for being a slow learner guys. I honestly didnt know much about electrical until this week. Now I'm finally starting to understand. I will have to open my headlight cover in the AM and check the connections in there. But I believe my problem lies with the connections next to the battery.

I wont know until I do another inspection and use my multimeter.

I noticed that the wires from the light strip he put on there for the back indicators has very skinny wires compared to the factory ones coming from the handlebar switches, could this also be the reason why the connection is faulty?

In the morning I can show you guys a closer look
 
650Skull said:
DG, (dark Green), Right turn signal............
Ch, (chocolate), left turn signal................
L, (blue and Y, (yellow) and B, (Black) to the taillight

Q: what has he got connected to the L and Y wires



Going by this pic...........it looks like the indicator wires are used for the taillight??????
20201014_212503-jpg.177188
I will show you a better look at the connections at 7:30 am (pst) when I am off work Skull. You may be right. I wish I could send a video but it's not possible
 
Two or three years ago I bought a 1970 Triumph 650 with unbelievably crap electrics. This was daunting as I knew nada, zilch, nothing about electrics. But needs must and you learn. Then it doesn't seem as daunting.
 
Two or three years ago I bought a 1970 Triumph 650 with unbelievably crap electrics. This was daunting as I knew nada, zilch, nothing about electrics. But needs must and you learn. Then it doesn't seem as daunting.
I'm lucky to be a very optimistic and positive person. Also lucky to have people like you guys who are patient and willing to teach all you know! I've already learned a lot by reading so much! Wiring diagrams are tough to read but I'm getting better. What confuses me is all the wires crisscrossing to different places on the diagrams, holy shit!
 
I work better with pics........

Yea the more pics the better..........close ups dont need to be so close, but just make sure they are large enough so they can be examined........latest pics are good.

wiring is a bitch then you die.......When i was trying to work out my loom i had trouble getting my head around transferring the diagrams to the bike.........diagrams do not relate to how a bike looks.......some days a i would have to stop for a few days and let my brain catch up.

I found continuity testing helped me as i followed the circuits and related them to the diagram
 
I work better with pics........

Yea the more pics the better..........close ups dont need to be so close, but just make sure they are large enough so they can be examined........latest pics are good.

wiring is a bitch then you die.......When i was trying to work out my loom i had trouble getting my head around transferring the diagrams to the bike.........diagrams do not relate to how a bike looks.......some days a i would have to stop for a few days and let my brain cat
I will definitely send clear and precise pictures later this morning!

When I first looked at a diagram my head almost blew off. It's so discouraging at first. I am currently watching a 40 minute YouTube video on motorcyle wiring diagrams go get even better understanding. I still have problems transferring it to the actual bike or visualizing it Haha
 
something else i found that made diagrams easier to understand........break up the different circuits......

EG; Power from the ignition, (brown wire goes to the Flasher relay.........power from flasher relay goes to indicator switch, (Brown/white wire). .........When the indicator switch is turned on it lets the power go out to the indicator's

Early loom74/75
75_76_XS650 B&C Wiring copy.png 75_76_XS650 B&C Wiring copy 1.jpg75_76_XS650 B&C Wiring copy.jpg 1.jpg
 
Yes
something else i found that made diagrams easier to understand........break up the different circuits......

EG; Power from the ignition, (brown wire goes to the Flasher relay.........power from flasher relay goes to indicator switch, (Brown/white wire). .........When the indicator switch is turned on it lets the power go out to the indicator's

Early loom74/75
View attachment 177200 View attachment 177201View attachment 177203


Removing all the other circuits helps understand the diagram so much more! I can actually see what goes where instead of trying to trace a million different wires on a diagram. I'll have to search and see what exactly the flasher relay does. I'm going to get my blinkers working today for sure!
 
The flasher relay don't do much. Power on, power off, power on, power off. That's how it reaches the handlebar switch. Probably a brown/white wire.
 
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