Boxerworks.com

Gidday Fellas,

All very interesting reading and yes now more confused than ever before, I still haven't got my head around lesson No.1 of Carbies and now all this electrical stuff raises its ugly but important head.

I think we can deal with the '28 Chevy OK, and probably the '81 R100...
NOW, what is broke? on what?
We will help you out.....which way did you come in?
Seriously (only joking) if the R100 runs, there isn't much that we will not miss telling you aboout.
If it does not run, you'll have to tell us why carbs are the problem first, then we'll lead you thru the land of volts and current.

Would I be close to right by saying that the 2 common problems are:
1. Rotor kaput. Usual sign is GEN doesn't light up when ignition turned on.
2. Diode failure in diode board. Usual sign is GEN light stays on or glows above 1500rpm
..and then there's all the other stuff.

Rotor failure - - R100; at night with my wife on the back about ten miles from home; made it home on the battery.

Condensor failure - - R60/5; stopped during a short ride; engine would not re-start; no warning; carry a spare now.

Battery failure - - R60/5; BMW wet cell; deader than a doorknob with no warning; close to home. Many years ago - - some
think the BMW batts are improved now.

Starter relay - - R60/5; in the garage.

SteveD...the voltage regulator is another thing that might go out on you...If you are near a town with an auto parts shop, no biggie. If you are going to the wilderness, it's a nice thing to have, too. (Get a list of OK-replacements by auto model...IBMWR web site tech notes has such a list)
Yes, the 2 item you mentioned ARE the ones that will cause you the most grief. Neither are easily replacable except from a BMW parts source...not necessarily a dealer...just a source!
On bikes with points and capacitor, I carry a spare set doubl-bagged in plastic. Usually it goes to help someone else!!

Rotor, Rotor, Rotor.