My 550 left me stranded

[musicman]

So go figure, I made a decision to try and ride the 550 the entire month of September and not get behind the wheel of my car, day one she died! Guess that wasn't going to happen

Figured I would post up and see if any of you had an idea where to start, since you guys have seen and done it all with these old GS's.

Riding along 50mph the bike just shut off, pushed it into a parking lot and got my multi meter out to start running some tests, my thought was the mosfet R/R croaked and I dis-charged the battery, but the battery was sitting at just about 13v across the posts. No dash lights, nothing works electrically. Sitting there I thought the main fuse was the culprit, it looked original and the end caps were corroded, the little metal bar inside was loose. Replaced that and still no dice, showing full battery voltage across the main fuse now. I checked all the grounds I could find, all seem in good shape. When I installed the R/R I made several new ground leads, including making new battery cables. R/R is wired direct from the stator too.

I don't really know where to start, since I don't have any lights I was thinking ignition switch? I've never heard of one failing though... tomorrow night I will tear the bike down and start tracing wires. Thanks for any help in advance!

[spyug]

What a coincidence, my 550 did the exact same thing to me today. It has been running well since I put new o-rings in the carbs a week or more back. I had it out yesterday for several hours with absolutely no issues and it started fine today.

I was planning a ride with two pals this afternoon and we got about 20 minutes from home. I'm riding along fine, absolutely no issues, then I notice my dash lights go out. The bike still runs but I've got no turn signals and likely no head or tail lights. I pull over and put the side stand down. Without dash lights I can't tell if I'm near neutral so I gently let out the clutch and she dies and of course won't restart.

Doing the same as you, I check all fuses and find them fine. I have almost 13 volts at the battery and I get similar voltage at the two red leads into the fuse block. No other voltage on any of the other leads with key in the on position. As we couldn't find any cause, my buds came back to the house and picked up the rescue trailer and as of now she is waiting in the garage.

As I had an issue before of loss of 2 volts at the kill switch, resulting in lowered voltage to the coils, I did the coil relay modification. While I didn't think that had anything to do with it, I did change to a spare relay but absolutely no change.

This is one of the weirdest issues I've encountered too but this bike has been a nightmare since the get go with several issues. I'm now feeling that when I get it sorted, it is going to a new home as soon as I can arrange it.

I'm sorry to hear of your issue. Please let me know if you solve the problem and i will do likewise.

Good luck.
Spyug

[Steve]

Using your meter or a test light (the light is easier and quicker), you have already verified that you have power through the MAIN fuse. Power then goes to the ignition swith and comes back to the other three fuses in the fuse box. See if you have power to them. If not, your problem is in or near the ignition switch. If you have power, check the other side of the three fuses. The three fuses are LIGHTS, SIGNALS and IGNITION, so if you only have one or two of them, you know what fuse is bad.

.

[Steve]

The bike still runs but I've got no turn signals and likely no head or tail lights. I pull over and put the side stand down. Without dash lights I can't tell if I'm near neutral so I gently let out the clutch and she dies and of course won't restart.

The dash lights, including the neutral light, work off the SIGNALS fuse (the second from the end), along with your turn signals, brake and horn. Your headlight and tail light are on another fuse and should have been OK. Your ignition fuse evidently blow, because you continued to run.

.

[musicman]

What a coincidence, my 550 did the exact same thing to me today. It has been running well since I put new o-rings in the carbs a week or more back. I had it out yesterday for several hours with absolutely no issues and it started fine today.

I was planning a ride with two pals this afternoon and we got about 20 minutes from home. I'm riding along fine, absolutely no issues, then I notice my dash lights go out. The bike still runs but I've got no turn signals and likely no head or tail lights. I pull over and put the side stand down. Without dash lights I can't tell if I'm near neutral so I gently let out the clutch and she dies and of course won't restart.

Doing the same as you, I check all fuses and find them fine. I have almost 13 volts at the battery and I get similar voltage at the two red leads into the fuse block. No other voltage on any of the other leads with key in the on position. As we couldn't find any cause, my buds came back to the house and picked up the rescue trailer and as of now she is waiting in the garage.

As I had an issue before of loss of 2 volts at the kill switch, resulting in lowered voltage to the coils, I did the coil relay modification. While I didn't think that had anything to do with it, I did change to a spare relay but absolutely no change.

This is one of the weirdest issues I've encountered too but this bike has been a nightmare since the get go with several issues. I'm now feeling that when I get it sorted, it is going to a new home as soon as I can arrange it.

I'm sorry to hear of your issue. Please let me know if you solve the problem and i will do likewise.

Good luck.
Spyug

That thing's been giving you a rough time for sure! My old '79 has been rock solid reliable until yesterday.

[musicman]

Using your meter or a test light (the light is easier and quicker), you have already verified that you have power through the MAIN fuse. Power then goes to the ignition swith and comes back to the other three fuses in the fuse box. See if you have power to them. If not, your problem is in or near the ignition switch. If you have power, check the other side of the three fuses. The three fuses are LIGHTS, SIGNALS and IGNITION, so if you only have one or two of them, you know what fuse is bad.

.

You nailed it in one shot, I completely forgot about testing the other fuses, I did not have power across the others. Thanks much Steve, that gives me a huge head start in what to trouble shoot next. I guess I'll look for continuity through the ignition switch in the appropriate positions.

[spyug]

Well there were no blown fuses. I did manage to test power going from the battery to the coil relay and from the relay to the coils but there was no voltage on the orange white lead coming from the switch. My best guess ( as I haven't yet fully explored things) is that its something to do with the switch itself or in the wiring where the leads to the coils are snipped off.

I will get on it again tomorrow and see where the voltage has gone, and yes i have had a rough time with this $500 bargain bike

Hopefully it will be a simple fix.

Cheers guys,
Spyug

[Steve]

At least you have it narrowed down to the run that goes from the MAIN fuse to the ignition switch, then back to the fuse box.

.

[Toadstool Food]

I guess I'll look for continuity through the ignition switch in the appropriate positions.

Musicman, the main switched power should be the solid orange wire. You will be able to check it at the flasher relay or stop lamp switch. If the ignition is good it will be hot with the key on. Be sure to check all the connectors north and south of the main fuse as well. My 550 has them on each side. They shuld all be hot all the time.

Toad

[musicman]

Decided to stay up late and play with the bike. I feel stupid now

Turns out it was the main fuse all along, my new one was defective. When I checked the main fuse, I checked across it, not inline, hence skipping it all together. Go figure, I was getting frustrated, I had a jumper wire out and jumped from one side of the fuse to the distribution block for the others, and my lights came back, connected the jumper to the other side of the fuse, no lights. Grabbed my meter, checked across the fuse, voltage, took me a minute to get my head working again, and realize what was going on. Once I did I pulled my new fuse and checked continuity, and no dice! So now I need to buy another fuse, haha. But otherwise there seems to be no problem, with a jumper in place everything works fine. I swear the old fuse looks original, the end caps are corroded and the filament inside had came loose, failure by being in service for 33 years perhaps? The filament didn't burn through like I would expect if it were overcharging. All the others look similar, going to replace all the fuses and clean the box up, and toss a pack of spares in my fairing, along with my jumper wire and a spare meter. Then back on the road it goes

So here's my word of advice, check to make sure your new parts are actually good! I almost started stripping the bike apart... sheesh.

[spyug]

Glad you found it. I'm off to a late start today and have yet to venture into the cave. It did keep me from a solid sleep and I think I'm a bit groggy and maybe procrastinating. I know I have to sort it but I'm tired of wrenching. On the other hand it looks like a wonderful riding day, cool and bright so i guess I should get to it.

Keep your fingers crossed for an easily resolution.

I'll let you know.

Cheers,
spyug

[spyug]

Well, it was an easy fix when I finally found it. A nick in the insulation of the leads going into the key switch causing a short. A bit of electrical tape and we are back in business.

I hope that's it for this season as I'm tired of wrenching. I'll save anymore of that for the winter months.

Now the only thing that bothers me is that while I know its sorted, this bike as given me so much grief I don't really trust it. The wife kinda summed up my unspoken feelings this morning when I told her it was sorted. She said, "Well maybe but you haven't ridden it yet and you better make sure your buddies are available to help if it breaks again". Sort of what I was thinking at the time as well

Maybe I should just park it til the spring market?

Cheers all
Spyug

[GateKeeper]

I hope that's it for this season as I'm tired of wrenching. I'll save anymore of that for the winter months.


Cheers all
Spyug

Ha.....your not done..wrenching..since your the guru of fixing these things, I am bringing you mine to sort out next.....

I have beer, cigars, slivovica, that should cover it....

I am going to go and work on the red heads Harley......painting and polishing is so much easier.....