Decades ago my R65 got hard to pull onto the stand. The fasteners wouldn't stay tight. The bolts bent and broke. The hole kept wearing bigger, making it hard to pull up. Finally I followed the advice of an article that appeared in the July 1983 issue of BMWMOA magazine. It involved creating a new cast iron bushing that fits in the hole, and different fasteners. Problem solved. I could provide the particulars if desired.

Hi there from the UK!

 

Update: My issues were caused by a failed, almost-new battery.

I spent a quality evening going over connections, cleaning things up, looking for shorts. Time well spent.

Eventually I thought to shoehorn in a known good battery off another bike, and sure enough, the charging system behaved as expected, sticking right around 12.2V at idle and consistently climbing to 13.9 off of idle.

I just got back from having the battery tested and it is confirmed bad.

Tiedie: I have my idle set to right around 1000rpm after it warms up (it is about 800rpm on startup). My gen light goes off as soon as the needle lifts above 1k. Sorry to hear about your wandering idle issues!

Hey all,

I just installed a voltmeter on my '82 R65LS to try to get a sense of the charging system, since I'd been seeing some erratic numbers when just running a handheld unit to the battery and revving the bike on the stand. I'd often see ~9.7V at idle as well as up into the rev range after starting, but eventually I'd start getting 13.6 or 13.7V off idle up into the revs. In all cases, the generator light on the dash glows at idle and quickly goes off above 1000rpm.

The voltmeter I installed is wired straight to the terminals on the battery via a switched relay, all new wiring by me. Today I did a bit of riding around to monitor things. I'm really confused by the numbers I'm seeing.

Today's ride (almost new battery fully charged):
Key on, voltage reads about 12.6V.
On startup, the voltage dropped to ~9.7V.
I rode away, and the voltage stayed right around 9.7V, even off of idle up to 3 or 4000 RPM.
After about a minute of riding, the voltage suddenly came up to 13.7V while cruising.
After this, the voltage would always stay right around 13.7 off of idle all the way up the rev band.
When stopped at idle, the voltage would hang around 12.4, then suddenly fall back off to 9.7 after about 30 seconds.
Taking off again, the voltage would go right back up to 13.7, sometimes 13.8 or 13.9.
After about 30 minutes of stop and go riding around town, the behavior changed.
Same behavior at idle, holding 12-something then dropping off to 9-something, but off idle, it would max at 12.7 or 12.8 throughout the rev range.
It did this until I got home.

Any ideas to explain this behavior? It's obviously capable of charging and did so through most of the ride, but that low voltage at idle and the eventual drop to 12.7-ish off idle is confounding to me. Planning to order Jones' Classic Boxer Charging straight away.

Any ideas?

Well being a 84 LS rider owner that is currently installing the EME elictronic ignition, I'm replacing my altinator rotor and diod board also with all new wiring.
But my question is what do you have your idle set for? I have mine set low at 750 to 800 but the manual specifically states 1000 rpm for idle. Witch brings me to my problem which is high idle after warm/hot to the tune of 1200 to 1500 rps which is my bean can having sticky brushes and springs butthat's my problem.
Sorry for getting off topic. Try turning up your idle first thing then look for other problems if your gen. light goes off at 800 to 1000 which is normal idle settings. Maybe your low voltage readings will improve.
Good luck and if I can help reach out
David