GS1000 G bump starts only.

[Vloukole]

Hi guys

My 81 GS1000 G will only start if I bump it. The battery can be fully charged and still wont start.
The bike starts easily when I use the bump start method and after that it will start every time with the start button.

I think it is either the battery or maybe a bad stator..?

Volts at idle is 12,4
Volts when bike is off 12,1
4000rpm volts at 12,8
When cranking the bike the volts drop to 8

Why does the bike start only after bump starting it, but never for the first time using the start button with a fully charged battery?

[tom203]

I'd say you got poor charging and probably a weak battery maybe because of that or it's just no good. But do the Quick test in this link and report all 6 results. Note that you need to start with fully charged battery for sleuthing, so charge it up first.

http://www.thegsresources.com/_forum/showthread.php?164993-Charging-System-QUICK-TEST/page2&p=1272192#post1272192

[azr]

That's very odd that the bike will not start with a fully charged battery, but once you bump start it after that it will start with the start button. Number one those are very poor charging numbers, there is obviously a charging problem and I would also suspect you had a contact issue somewhere, possibly at the start button itself. It would be a good idea to pull apart your start button and do some cleaning, as well as your ground connections, etc....you'll have to do some of this anyways to diagnose your charging issue.

[Vloukole]

Thanks for the quick response.

I have an update: A while ago I saw that only two of the three wires from the stator was connected to the r/r. I left it alone cause the bike ran well. Tonight I decided to do further investigation and had a look at the wiring diagram. The male connection of the third wire was connected to a wire the same colour (white/yellow and red) as it. The wiring diagram showed that the third wire from the stator (green and yellow) had to be connected to the white and red wire from the r/r. So I connected those two wires and there it was... charging while idling at 13.8v at the battery.

So now I have another wire without a male connection. It is yellow and red and is part of the main harness. Any idea?

[Grimly]

I'm not sure of the wiring for the S.A. market, but if your bike was wired for the headlamp to be on all the time, the loop of the third phase from the stator would have went up to the headlamp shell and been returned, without ever going to the switch - ie, permanently on, just like the headlight. On bikes where the headlight is voluntary, the third phase loop gets switched in and out as you turn the headlamp on and off. It's a crude but effective way that Suzuki hit on to attempt a way of taming the excess currents in the stator and reg-rec.
So, if you now have all three stator legs going to the reg-rec, that's good, but if you're running a shunt type of reg-rec, make sure you run the headlamp as much as possible. This is totally avoided by fitting a series reg-rec.

[Vloukole]

Thanks Grimly. It still has the original reg/rec.