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Main Area => General GS500 Discussion => Topic started by: Atesz792 on July 28, 2022, 12:17:12 AM

Title: Intermittent starting problem
Post by: Atesz792 on July 28, 2022, 12:17:12 AM
Hi all!
It's been a while...
I have a problem with starting. Sometimes I push the starter button and absolutely nothing happens, even while jumping from a known good battery it doesn't turn the engine at all, the lights work though.
This morning I shorted the starter relay with a screwdriver and it turned the engine nice and quick, but there was evidently no spark. Ignition was in the on position, transmission in neutral, green dash light verified this.
Then I picked her up from the side stand, put her on the centre stand, and voila, she started right up.
Then had to switch off for a minute, then again nothing happened when I pushed the button. Sidestand down, sidestand up, started again.
All this happened in neutral.
Question is, can I be sure the sidestand switch is faulty, or are other factors at (in?) play here, too? IIRC sidestand position shouldn't matter when starting in neutral... Or should it?
Title: Re: Intermittent starting problem
Post by: petro on July 28, 2022, 07:57:06 PM
You're right that when in Neutral, the bike should start regardless of sidestand position.  You mentioned that the N lamp is coming on as expected.
I had a look at the wiring diagram and the neutral switch wire 'branches off' via a couple of diodes. One goes to the N lamp, and the other goes to a 'sidestand relay'.  So it's possible to have a defective sidestand circuit prevent starting, even if the N lamp is on.

IF I have this right, you may want to check the sidestand relay and engine kill switch.  If there's a flaky connection somewhere, or a bad relay, simply moving the bike might be enough to affect it.
Title: Re: Intermittent starting problem
Post by: drey6 on July 28, 2022, 10:59:59 PM
My 1986 Ninja had this issue. Sidestand switch was gummed up. Wd40 and some "working" of the switch fixed it for me
Title: Re: Intermittent starting problem
Post by: Atesz792 on August 08, 2022, 01:51:18 AM
Sorry for being late to answer but I haven't ridden since the op.
I went on to start 5 minutes ago and again, lights come on, engine doesn't move.
Sidestand up or down, clutch in or out, in neutral or in gear, on centre stand, and combinations of the above, nothing.
Then I pushed the bike back in the garage, put it on the centre stand a 3.8Amp battery charger, and at the push of the button she started right up. Remember last time jumping from a charged car battery it didn't even try to start.
I'm at a loss here. If it was the battery, it should have started last time from a big battery with presumably high CCA.
If it was anything else, it shouldn't have started now on the charger.
Any thoughts? I bought a second hand sidestand switch but haven't installed it yet... Not totally convinced that it might help.

Edit: installed new-to-me switch. Fingers crossed...

Edit #2: She started up, ran for 2 hours.
I think there might be a different issue: I tried starting with no sidestand switch attached, and she started up in neutral but not in gear. So I would think that a faulty sidestand switch (open circuit) shouldn't stop me from starting in neutral, if not having one installed at all doesn't stop me either.
Also she has never cut out while riding or stuff like that.
Now I have a different problem: while attached to the wiring but not installed on the bike, the 'new' switch worked as it should, but now it's installed on the bike and it didn't kill the engine when I put the bike on the side stand, in gear, after the ride. :dunno_black: nevermind this was user error, it was in neutral after all.
Could my original issue be a clutch switch hack that started to intermittently not work?
That's my next idea, because once started it's business as usual. Checked the clutch switch, connectors are attached to it but if I pull them apart the bike still starts so I think it's bypassed somewhere else, any ideas?