bike no workie re post from wrong section lol

[sid693]

my 78 gs550 is not turning on. by that i mean it seems like the switch is off. at first i thought it was the battery but put a good one on and it is doing the same thing. when i turn the key to the on position my gauge lights and gear light does not come on. i kicked it over and the lights come on but it bogs down like the ignition is off or it has no fuel. the bike was running fine prior to this. it is a new bike so i am pretty much done with bikecliffs noob to do list. i was thinking it was the ignition switch but i checked it and the ohms look good. i checked what i thouhght was the ignition which is where the battery power wire hooks too and it had ohms of around 3.4. thats as far as i got for me expertise. i tried pulling up the schematics from bikecliff site but it was way to fuzzy to make out the lines and such so i just set it aside. i used the 77-82 service manual for the schematics. any help or ideas would be greatly apreciated. i will try to see if the plugs are firing tonight when my gf gets off work. last night i couldn't get a hand for someone to hold the plugs to see if they are firing.

[koolaid_kid]

You can do the plug spark test on your own.
If you still have the clutch interlock connected, where you have to hold the clutch in for the starter to engage, just zip tie the clutch handle to the grip where the clutch handle is always engaged.
Then pull a plug, ground it to one of the fins, and press the starter button. You should see a blue or white spark when it turns over. A red or yellow spark indicates low voltage at the coils. No spark, of course, means troubleshooting the ignition system.

[Steve]

Have you verified that you have a good battery?

It is not enough to simply check the voltage, you also need to apply a load.

I helped diagnose a bike just yesterday. The battery's no-load voltage was 12.78, which is about right for an AGM battery. Turned the key ON, there was NOTHING. No lights, nothing at all. Turned the key OFF, checked the voltage, still over 12.7. Kept the meter on the battery while turning the key ON again, voltage instantly went to ZERO. Ran jumper wires from my van, the bike started up just fine.

You have to check the battery with a load.

.

[Redman]

from other posting:

Sid,

Welcome to GSR.

Bike no workie?
Sounds like electrical problem.
Good that you have a meterie so you can checkie things.



Hold the plug? ... How? ( chuckle chuckle )


You say you are measuring ohms...
So apparently you have a meter.
Yes, measuring ohms is one way to troubleshoot things (with power off).

Another way would be to measure voltage at various places. Might be easier for discussion purposes to measure voltage.
At battery.
At the main fuse.
At other side of main fuse.
At ignition switch.
At other side of ignition switch.
At ignition coil.
At other ignition coil.

(I am not that familiar with wiring of the 77-79, To be quoting wire colors for this and that other things to check. One fuse only, right? .)

Are trying to start at the battery, and work your way along the circuits to see where you are loosing it.

WHen you do detect power at some particular devive with the meter, also, be concerned about where you have the meter negative lead, move it from the battery negative to the frame ground and move to wiring harness black/white and/or the ground of the device to see if measure the same voltage. If not the same, well then problem might be in the ground wiring to that device.


That thing the red battery cable connects to is the starter solenoid. The big red wires are for the starter motor, The smaller red wire is what provides power TO all the bike wiring (other than starter motor). THe other small wire is FROM the starter button.

Tell us more what you find.

.

[sid693]

the bike wont start with the electric starter but i think i found the problem or part of the problem. the wire from the battery is really corroded and has only a few strands of copper that are real green. gonna change out that line and see how she likes it. thanks for the input and if i start chasing my tail i will post again.

[Redman]

the bike wont start with the electric starter but i think i found the problem or part of the problem. the wire from the battery is really corroded and has only a few strands of copper that are real green. gonna change out that line and see how she likes it. thanks for the input and if i start chasing my tail i will post again.

Is not too often that can trouble shoot an electrical problem with your eyeballs. Most often need a meter.

Bad connection usually cause symptom of things seeming to be okay.. until put a load on it, like turning on ignition switch, or headlight, or hitting starter button. Which is pretty much same symptoms of weak battery or internal problem in battery (like Steve mentioned.) (I would never disagree with Steve.)

But if you say is only a few strands of copper left in the battery cable, yah, that is a problem. But a few strands could still light up instrument lights, but then everthing dropp off when put on more load. Maybe you have just a few strands left in the cable .. and the connector at end of cable not making good contact either due to the corrosion.

Yah, replace that corroded-damaged battery cable (inspect the other one too, and the one to the starter motor). And inspect where the ground cable is bolted to back of engine.

As a test, maybe can use a jumper cable to bypass/replace your suspect cable and see if things work better.

Do post an update of what you find (before chasing tail).

.

[pdqford]

But if you say is only a few strands of copper left in the battery cable, yah, that is a problem. But a few strands could still light up instrument lights,

Just want to give a +1.

If your using a test light or a meter looking for voltage, those few strands can pass enough current to light up your test light or be read by the meter and fool you into thinking the circuit is okay. But if you test the circuit under load looking at voltage DROPS, you won't get fooled.

[sid693]

so the journey continues... i replaced the line and threw a new battery in the bike and it still doesn't want to start. i checked the new battery to make sure it wasnt bad with a multimeter and it holds the load unlike the old battery. it seems to be making a clicking noise at the starter solonoid. is there a way to check the solonoid? the cable positive cable was replaced due to only holding on by a few strands and being really corroded and green... may not have been my problem but i replaced it anyway. thanks for all the feed back

[koolaid_kid]

Normally a clicking sound means low voltage at the solenoid. However, since you just replaced the battery do this: Jump across the two posts on the solenoid using a screwdriver or a pair of pliers. If the starter turns over, that means you are getting full voltage at the solenoid. Then put your voltmeter on the small wire on the solenoid and press the starter button. If you get ~12V then check the ground wire on the solenoid. If it is good, then the solenoid is bad. Go to a hardware store and buy one for a garden tractor for ~$15 and you should be GTG.

[Redman]

....
................ it seems to be making a clicking noise at the starter solonoid. ................

Well, the cable needed to be replaced, and has made some progress.

Now do you get lights and such?

If solenoid is clicking, then you know the starter button circuit to the solenoid is good.

You can try jumping around the solenoid by jumpering between the two big termionals like KK suggest. If it cranks over then you know solenoid is not doing what it is suppose to.
If you jump it and starter doesn't crank, then problem is probably something other than the solenoid. Like starter motor itself, cable to starter, or battery negative cable to the back of the engine.

You can try checking voltage on both of those posts too, to check if the solenoid is doing what it is suppose to.

Did you check the battery negative cable that goes to back of engine case?

[sid693]

will get that knocked out tomorrow. also thanks for the info on the solonoid. i didnt think of jumping the solonoid. i used to do that on my dads old '65 gmc pickup. ill give it a shot and hopefully get this issue resolved and back on the road. thanks again for all the help

[Redman]

...
..... i didnt think of jumping the solonoid. ......
...... ill give it a shot and hopefully get this issue resolved ......

We are suggesting jumping the solenoid as part of troubleshooting to help determine where the problem might be.
Not suggesting that jumping the solenoid is the resolution to the problem. If you do that too many times (and once may be too many) you can bugger up the treads on the post.

.
...
...If you jump it and starter doesn't crank, then problem is probably something other than the solenoid. Like starter motor itself, cable to starter, or battery negative cable to the back of the engine......

Let us know what else you find.


.

[sid693]

i meant about jumping the solonoid to see if it was bad/going bad. i didnt mean jumpering a set of leads around the solonoid. lol that would be a real bad situation.

anyway new update. I checked voltage at the battery side of the solonoid and i am getting a solid 12. as i pressed the start button and checked the starter side of the solonoid i got a solid 12, then i checked the other little wire, not sure what it was and i got around 9-10v out of it. then i checked the ground and made sure it was grounded to the frame and it was with 0 ohms. i am thinking its the starter. any suggestions? thanks again for all the input. i just hope i get this thing figured out cause it is starting to be a pain in my booty

[Big T]

Does the solenoid click when you press the starter button?

Did you jump the solenoid?

[sid693]

the solonoid clicks when i press the start button and when i jump it with a screw driver it doesnt do anything. i was thinking it should click but it doesnt. i am thinking of replacing the solonoid and seeing what it does.