I've got a 2008 gs500, which (so far) has been the most reliable bike I've ever owned. I use it for a daily commute and it's the dogs.
But, today out of the blue it completely died.
I'd been riding it all day, stopped at the pharmacy for 10mind and when I came back it wouldn't start - no lights (neutral, headlights, brakes or otherwise), no attempt to start over, utterly devoid of life.
Had anyone experienced this before?
I managed to jump it and get home (500 yards) but as soon as the revs dropped it died again and wouldn't start, plus when it was going the power was all over the place and the rev counter was jumping about. I've checked the battery (13ish bolts holding, cleaned the terminals), the fuse, the clutch switch, engine cut off switch, sidestand switch and wiring. Still nowt.
Would appreciate any ideas, my current concern is foul play given that it happened so bloody suddenly. As I said, I use it for work every day so it's v frustrating it being dead n all.
Cheers!
Sounds like a straightforward case of a dead ignition coil.
On the newer GSes the rpms are measured off one of the ignition coil wires. An intermittent ignition coil accounts for the uneven power, the jumping tach, the difficulty starting, and the difficulty idling. Ignition coils can and typically do fail suddenly, they are affected by heat cycles so your coil was probably on its last leg and the heat from your last ride and the 10 minute break finally killed it.
If it were my bike I would shop for a used ignition coil based on the symptoms and without testing anything else.
All in all, its better that you aren't dealing with a dead owner and concerned bike :)
Thanks very much, that's really helpful.
I'll let you know how things progress. :thumb:
Bad news - new ignition coil arrived in the post today. I tried in both positions but still nowt. Very upsetting.
Any other ideas?
Also does anyone know how to test the secondary winding resistance? I've tested between the end cap of the HT lead and both of the primary winding terminals but I haven't been able to get a reading on any of the ignition coils I have (3 now). The primary winding appears within the normal range (3-6 Ohms) on all 3.
Cheers
Sorry I misled you. I should have tempered my confidence when it was someone else's wallet...
Hahaha, no worries at all. I'd much rather take a £10 gamble and get to spend an afternoon tinkering than run straight to the mechanic. I appreciate any suggestions!
At the minute I'm thinking a wire somewhere has given up, given the abruptness of the failure. Any common places where these bikes fail?
I will start with; This may not be your problem and I am not a mechanic, just a tinkerer.
Several years ago I had almost the exact same experience. Stopped at the store on the way home, came out and the bike would not start. Managed to bump start and get it home. Battery was fine. After researching and after troubleshooting I ended up replacing the stator coil and have had no trouble since. There is documentation how to test for this with a multi-meter somewhere around here. Definitely do the test first as this is a more expensive part.
Quoteno lights (neutral, headlights, brakes or otherwise), no attempt to start over, utterly devoid of life.
I had that issue a little while back. Maybe this may help! I ended up having a bad rectifier that sent too much voltage to the battery boiling out the acid. So the battery read the correct voltage but didn't have the amperage to start the bike... Or do anything.
http://gstwins.com/gsboard/index.php?topic=70311.msg845256#msg845256
Ok. Let's get to the bottom of this.
Since your tach was going crazy during your ride I still think you are looking at an electrical problem. Here is my advice for diagnosing an electrical issue.
First check your battery it should read a little over 12V while off. If you can get the bike to idle the battery should read 13.5V to 15.5V while running. Below 13.5 indicates a bad alternator, above 15.5 indicates a bad rectifier. You might be able to take your battery to an auto parts store and have them test it.
Pull both spark plugs and connect them back into their spark plug wire. Hold the end of the spark plug against the engine (so that it will create an electrical circuit) and watch the gap for sparks while you hold the starter button. Verify that both spark plugs are sparking while holding the starter button. With the engine cylinder open like this fuel *shouldn't* travel from the carbs to the cylinder but I suppose that might be possible. Wear eye protection for sure.
If both spark plugs spark that means that the plugs, wires, coils, and wiring from the CDI to the coils are good. It is possible though unlikely that the signal generator or the CDI may be bad. Check those components or skip to the fuel sections.
If neither spark plug sparks then skip down to inspecting the signal generator.
If one spark plug does not spark then you have a "dead cylinder." Swap the positions of the plugs and see if the dead cylinder jumps to the other side. If it does jump then that means the spark plug is bad.
If the dead cylinder does not jump then pull the spark plug wires out of the coils and swap those, the spark plug wires will come out if you pull them straight out of the coil. See if the dead cylinder follows the spark plug wire.
If the dead cylinder does not jump then repeat this process with the coils (you already did this step). While the coils are out check the resistances in them the primary winding (the coil leads) is 3 to 6 ohms and the secondary winding (the spark plug wire and coil lead) is 18K to 30K ohms.
The next thing to check are the signal generator sensors. You can check the continuity of the wires, the condition of the solder joints, and the resistances in the sensors (250 to 420 ohms) if you like.
Check the CDI. Inspect the ground wire from the CDI to the negative terminal of the battery. If the wire is loose, frayed, cut, etc this will inhibit sparking. Most places you look will tell you to inspect the CDI by replacing it which bothers me. It is possible to check the CDI by exploiting the fact that there are two independent circuits inside (if you're on the older version of GS500 that has two signal generator sensors, this process won't work on the newer single sensor systems.) Unscrew the signal generator sensors from the metal plate they are mounted to and swap their positions. Swap the white and black/yellow wires to the coils. This effectively swaps which circuit in the CDI is driving which cylinder. If the dead cylinder jumps your CDI is bad. Remember to undo the sensor and wiring changes.
Update, with photos!
So I decided to follow up on 89500inPA's suggestion as it sounded most like my issue (plus I can't get the bike to idle, ones its been jump started it has to have the throttle wide open or it dies).
The following showed me how to test the alternator: http://gstwins.com/gsboard/index.php?topic=38480.0
Initially it was a struggle identifying the alternator wires - however following the diagram at the top of the post it showed that of the 5 wires leaving the rectifier, 3 were going straight to the alternator. On my bike it appears that all the alternator wires are yellow (as opposed to white/blue, white/green etc.) so I unplugged the connector and tested all three terminals against each other.
As far as I can tell, the resistance between each of them should be close to 0. I found that between terminal 1-2, and 2-3 the resistance was about 18 Ohms, and between 1-3 it was about 6.
Here are my questions:
1. Am I testing the right wires? - I'm going to try and upload some images once I figure out how.
2. Does the resistance between the terminals indicate a dead stator coil? As far as I'm aware the stator is a huge length of copper wire wound round and round - would there not be some inherent resistance in that circuit due to inefficient connectors etc? My concern is that 18 ohms doesn't sound like much of a resistance, but it could be when its a stator.
(http://s31.postimg.org/u3hyc8zi3/20160422_094553.jpg)
So, starting at the rectifier, I chased the 5 wires through the harness to the two plugs.
I pulled apart the plug with three wires going in, the male side of the plug had 3 yellow wires all of which went down towards the alternator
(http://s31.postimg.org/3vy2ck88r/20160422_094604.jpg)
Heres the plug which appears to go to the alternator
Then I tested each of the terminals
(http://s31.postimg.org/ipxfsoypn/20160422_094656.jpg)
(http://s31.postimg.org/ixzrx6bp7/20160422_094709.jpg)
(http://s31.postimg.org/qz1yl49ff/20160422_094802.jpg)
Forget all this talk about coils, modules and reg/rects. The battery is the component most likely to fail in the charging system, its why your dealer stocks dozens of them and not dozens of coils and reg/rects and it should ALWAYS be the starting point when diagnosing starting/charging faults.
Static voltage figures do not mean its serviceable, what matters is its ability to deliver current under load and the only way to determine this is by having it load tested at a shop. Unless of course you have access to one yourself. If it fails the test get a new one, if it passes you can start looking elsewhere.
If you are feeling brave connect your jump leads up to the battery and VERY QUICKLY brush them together, no or very weak sparks probably means its dead but again this is only a indicator and a substitute for a proper load test.
BTW Its unusual to see one suddenly fail but its not by any means impossible if something inside the battery suddenly breaks or rattles loose. You carry on running off the power the alternator puts out but once the engine slows or stops there will be nothing there.......and isn't this a symptom?
In fact the more I think about it......forget about the load test, just get a new one :thumb:
Maybe not helpful, but these bikes vibrate a lot and if you're really feeling lost it's probably worth a comprehensive visual inspection and cleaning of all the wiring and pods. I had intermittent no-start issues for months until I finally opened the starter switch pod on the handlebars and cleaned it out - problem disappeared. Intermittent electrical issues can cause all sorts of weird symptoms. Anyway, visual inspection is free so I'd start there (and a full battery test).
Spent 3 days chasing wires due to very similar symptoms (except I had neutral and oil light, nothing else) found a severed wire on the ignition switch and a dirty ground connector right next to the battery, electrical faults are so damn frustrating!