I'm getting two '80 GS850G's and an '82 1100G ready to go on a cross counry trip next week. I have never had a charging problem ever, but did some inspection and testing on these bikes, anyway. On one of the 850's, all the connectors showed signs of overheating, and the main power connector out of the R/R was totally cooked. This bike was charging at about 13.5 volts at 2000 RPM and about 12.9 at 4000. The 1100 was working about the same, but the connectors were not so obviously burnt. Grounding is really iffy as designed, IMO, especially on the 850 Several importand grounds are to the battery box, and to the ignition module mounting plate on the battery box. The battery box and plate are not very well grounded to the frame and battery from the factory, imo. I installed bonding jumpers between them and the battery. The connectors were cleaned and reinstalled. I also installed Duaneage Honda R&R's on these bikes. Both are now charging well within specifications.
So, my observations are two:
Like many have written, bad connections, which are free to fix, are killing your charging system, and you can't tell until it is dead.
Extra grounds look like cheap insurance.
One more valve adjustment and one more charging system check out to go, but my other 850 has only 5000 miles and still looks new.
For what its worth, I think its way easier to remove the battery box than to try to change the R/R in place. Nice place for phillips head screws by the factory.
So, my observations are two:
Like many have written, bad connections, which are free to fix, are killing your charging system, and you can't tell until it is dead.
Extra grounds look like cheap insurance.
One more valve adjustment and one more charging system check out to go, but my other 850 has only 5000 miles and still looks new.
For what its worth, I think its way easier to remove the battery box than to try to change the R/R in place. Nice place for phillips head screws by the factory.