1996 GS500
Bike sat for 5 years. I've done all the normal stuff: carbs cleaned, new plugs, checked valves, brakes, etc.
It's now time to install a battery and try to start her up. Ordered a new AGM battery, installed it and initially got dash lights, headlights, turns signals, horn, etc.
When I hit the starter button, I lost everything.
Checked the fuse ... all good.
When turning on the key, I initially got some lights, horn, etc., but the starter wouldn't turn. I did some battery tests (see below) and now I get no lights or anything when I turn on the kiey, BUT ... it places a draw on the battery. That tells me the key switch is working, right?
I guess the kill switch could be an issue. I can also hear a humming somewhere around the engine when the key is on.
To test the battery, there were 4 readings: static battery voltage, voltage after charging, voltage after sitting 12 hours, and voltage with a load. Here are those results:
Test #1: 10.8V
Test #2: 12.51V
Test #3: 12.74V
Test #4: 06V
After trying only once, the battery voltage dropped to 10.3V. When I turn on the key, it drops to 0.3V (which tells me the key switch works because it places a load on the battery).
I tried checking voltage going TO the main fuse/solenoid, but I'm getting nothing there. Does that mean the kill switch could be bad?
check the wiring diagram and measure resistance.
I think you could be having a bad ground or something shorted.
1st clean all the connectors
measure continuity for 12v path
also measure resistance to ground looking for leaks
battery is directly wired to starter relay so jumping the big two cables should engage the electric starter with everything off.
-Battery has enough juice
-starter is in good condition(measure resistance to ground)
-no other leaks(Parasitic loads) drawing power(robbing juice)
-complete circuit, check for thick grounding wire from engine to negative on battery.
Then you have the ignition side to worry about so sparkplugs fire each cylinder.Thats once you turn the key.
First i would concentrate in making the engine spin and retaining charge.
Sounds like a bum battery to me, 10.8 is already in the region where it's totally empty and sulfating. Is that the voltage that you received the battery?
I would check with a known good battery. If push comes to shove carefully run jumpers from your car battery. But don't start the car! (Folks sometimes think that having the donor vehicle running is good)
Battery Stuff (the vendor) agrees that it's a bad battery. Unfortunately, they're on backorder.
If I leave the battery on the charger, I can get weak lights, horn, etc., and a very weak buzz when I hit the start button. Only one or two tries, or even cycling the key a couple of times, and it's too dead to do anything.
Glad you had the reflex to doubt the battery, folks have spent money chasing invisible gremlins refusing to believe a new battery is bad.... DAMHIK......
Quote from: scott-s on May 09, 2024, 09:10:21 AM4 readings:
static battery voltage,
voltage after charging,
voltage after sitting 12 hours,
voltage with a load.
Here are those results:
Test #1: 10.8V
Test #2: 12.51V
Test #3: 12.74V
Test #4: 06V
After trying only once, the battery voltage dropped to 10.3V. When I turn on the key, it drops to 0.3V (which tells me the key switch works because it places a load on the battery).
I tried checking voltage going TO the main fuse/solenoid, but I'm getting nothing there. Does that mean the kill switch could be bad?
why it rises after sitting, very very strange.
Anyways, its fixed.
How long can you let it sit connected without cranking and still have enough power to start? for me its 2 weeks maximum. 10 days to be safe.