Electrical issue?

[83GS1100E_Tornado]

Friend of mine has an 83 GS750ES, and is experiencing some electrical issues, we think. First off, when he first got the bike he had to rebuild the carbs to get it running, it had been sitting for a few years. Once he got it running, he noticed the new battery didn't last long before it went dead. The first thing he did was replace the rectifier, because the previous owner said he had replaced the stator already. Well, the battery hasn't gone dead since he put the new rectifier in about 6 months ago, so he thought it was "fixed". Now, he's been complaining about the bike "puttering" out at high RPM. In other words, the bike runs good until he get's it up very high in the RPM range, and then it misses. Carbs seem to be OK, he took it to a local shop after giving up on it, and they're telling him it's probably the stator? The shop said that on the voltage test, it reads 13.3 to 13.5 at idle, but when they rev the bike up, it doesn't go up at all, just stays right around 13.5. Could this be enough voltage to keep the battery charged, yet not enough to cause a "sputtering" issue at high RPM? He just wants to make sure they are not just trying to sell him a 300 dollar stator job, if this could actually cause the problem he's having. Any help would be great appreciated, thanks!

[steve-lloyd]

Friend of mine has an 83 GS750ES, and is experiencing some electrical issues, we think. First off, when he first got the bike he had to rebuild the carbs to get it running, it had been sitting for a few years. Once he got it running, he noticed the new battery didn't last long before it went dead. The first thing he did was replace the rectifier, because the previous owner said he had replaced the stator already. Well, the battery hasn't gone dead since he put the new rectifier in about 6 months ago, so he thought it was "fixed". Now, he's been complaining about the bike "puttering" out at high RPM. In other words, the bike runs good until he get's it up very high in the RPM range, and then it misses. Carbs seem to be OK, he took it to a local shop after giving up on it, and they're telling him it's probably the stator? The shop said that on the voltage test, it reads 13.3 to 13.5 at idle, but when they rev the bike up, it doesn't go up at all, just stays right around 13.5. Could this be enough voltage to keep the battery charged, yet not enough to cause a "sputtering" issue at high RPM? He just wants to make sure they are not just trying to sell him a 300 dollar stator job, if this could actually cause the problem he's having. Any help would be great appreciated, thanks!

This is very unlikely to be a problem with the stator. 13.5 volts is adequate to keep the battery charged.
It sounds more like a fuel starvation problem. It could be the vacuum operated fuel tap is not delivering enough fuel to feed the motor at high revs.
Try running the bike on the "prime" position, which doesn't depend on vacuum. If it cures the problem, then you will need a fuel tap repair kit, assuming you have checked the vacuum pipe from the tap to the carbs for condition and tightness.

[renobruce]

Use the stator papers in the GS Garage. That should determine your problem if it's electrical.

[83GS1100E_Tornado]

I know one thing, he is running one of those inline fuel filters on the main fuel line, because he wasn't sure of the condition of the tank, and didn't want to risk getting junk in the carb. I wonder if this could be causing the starvation issue?

[83GS1100E_Tornado]

Use the stator papers in the GS Garage. That should determine your problem if it's electrical.

I read the stator papers, and according to them, if the voltage doesn't rise when the bike is revved, it probably needs a new stator. But since the battery is staying charged, I wasn't sure if this stator issue could be causing the high revving cut out that he described to me. That's why I asked the question here. It very well may need a new stator, according to the stator papers. We're just wondering if there is another issue that could be causing the cutting out, or if the stator replacement will fix it. I guess he won't know for sure until the stator is replaced. In a perfect world, he would like to fix the cutting out issue first, and replace the weak stator at another time, because after all, the battery is still charging fine. He's running low on cashola right now, being Christmas time and all, and obviously wants to spend as little as possible! Thanks for the info guys!

[SqDancerLynn1]

Filter could definately cause a high rpm problem. Temp remove it & try the bike without it. Properly sealed airbox is also mandatory