I am interested to hear from anyone who has an F650GS with a volt meter and has had a charging system problem in the past. I am trying to interpret some voltage readings I am getting. If you had a voltage regulator or alternator go out, what voltage readings were you getting prior to the failure?
On the return leg of a 2 day trip a couple weeks ago, I started getting voltage readings on my Battery Bug that were varying a lot more than normal. When riding on the highway, voltage is usually 14.0, if I do not have the Gerbing gear on, and varies only one or two tenths of a volt. The readings I was getting were dipping down to 13.8 and bouncing up and down about every second. The bike starts and runs fine.
My wet cell battery was over 2 years old, so I suspected the battery and replaced it with a Scorpion AGM, but the voltage variations continue. I don't regret replacing the battery, though. I was getting tired of disassembling the bike every three months to top off the water in the battery and was planning to change to an AGM battery anyway.
Went for a ride yesterday, 1 hour over, 2 hours there, 1 hour back, and on the way back, the voltage was dipping as low as 12.8 all the way back up to 14.0 or 14.1. When the bike is off, the voltage reading is steady. The variation is not all the way from the high to low all at once, it will read like, 14.1, 13.9, 14.0, 13.5, 13.8, 13.1, 13.7, 12.9, 13.3, 13.8, 14.0, 13.7. The Battery Bug display alternates between a percentage reading and the voltage once each second, so you can't see what is going on during the 1 second interval that the percentage is displayed, but just about every time the voltage is displayed it is a different reading than the previous one, usually between 1 and 4 tenths of a volt up or down.
As a double check, I plugged a second volt meter into my accessory socket and used a velcro wire tie to position it on the handle bars where I can see it, just to make sure the problem is not with the Battery Bug itself. On the way to work today, the two volt meters were agreeing, but I did not get the voltage variation. I have a short ride to work, so the bike doesn't get up to full temperature. I will go for a longer ride this afternoon to check it out.
I am interested to know if this voltage variation is a known symptom of a failing alternator or voltage regulator. I ride in the winter and use Gerbing gear, so if my alternator is on the way out, I would rather fix it before it fails completely. I am a 1:45 ride to the nearest BMW dealer, so it would be better to fix this before it gets really cold.
On the return leg of a 2 day trip a couple weeks ago, I started getting voltage readings on my Battery Bug that were varying a lot more than normal. When riding on the highway, voltage is usually 14.0, if I do not have the Gerbing gear on, and varies only one or two tenths of a volt. The readings I was getting were dipping down to 13.8 and bouncing up and down about every second. The bike starts and runs fine.
My wet cell battery was over 2 years old, so I suspected the battery and replaced it with a Scorpion AGM, but the voltage variations continue. I don't regret replacing the battery, though. I was getting tired of disassembling the bike every three months to top off the water in the battery and was planning to change to an AGM battery anyway.
Went for a ride yesterday, 1 hour over, 2 hours there, 1 hour back, and on the way back, the voltage was dipping as low as 12.8 all the way back up to 14.0 or 14.1. When the bike is off, the voltage reading is steady. The variation is not all the way from the high to low all at once, it will read like, 14.1, 13.9, 14.0, 13.5, 13.8, 13.1, 13.7, 12.9, 13.3, 13.8, 14.0, 13.7. The Battery Bug display alternates between a percentage reading and the voltage once each second, so you can't see what is going on during the 1 second interval that the percentage is displayed, but just about every time the voltage is displayed it is a different reading than the previous one, usually between 1 and 4 tenths of a volt up or down.
As a double check, I plugged a second volt meter into my accessory socket and used a velcro wire tie to position it on the handle bars where I can see it, just to make sure the problem is not with the Battery Bug itself. On the way to work today, the two volt meters were agreeing, but I did not get the voltage variation. I have a short ride to work, so the bike doesn't get up to full temperature. I will go for a longer ride this afternoon to check it out.
I am interested to know if this voltage variation is a known symptom of a failing alternator or voltage regulator. I ride in the winter and use Gerbing gear, so if my alternator is on the way out, I would rather fix it before it fails completely. I am a 1:45 ride to the nearest BMW dealer, so it would be better to fix this before it gets really cold.
