Charging light on constantly - what to check first?

[wheeler7664]

The bike is a 64 R27.

While completing the fall 2010 Motogiro USA, the bike developed three problems, for each of which I may seek help here to diagnose.

The first of these is that the red charging light started to be illuminated all the time, no matter the rpm.
The red light has always illuminated at idle, but previously would extinguish with a little rpm.

Bike has a fresh, fully charged battery. I rode about 150 miles over a couple of days with this battery before the charging light problem started.

I've looked over all the wiring in the headlight shell and the vicinity of the battery and have found no loose connections, frayed wiring, etc.

I have little or no experience and competence in motorcycle electrical systems and may end up taking the bike to Bench Mark Works to remedy this and/or all of the problems, but I really need to learn to do more of my own repairs so any help here will be much appreciated!

Can anyone suggest a relatively simple way to diagnose this electrical problem or suggest one or two easily replaceable and relatively inexpensive parts that I might replace to narrow down the possibilities?


(The other two problems were that oil began to blow all over the bike from the cylinder rearward and then late in the day the bike began to jump out of gear randomly and a few times while riding at moderate rpm the clutch seemed to engage, disengage, and slip without any lever input. No more than a cup of oil total was blown out during the day, and I think I've isolated that to a loose push rod cover. The gear and clutch problems occurred during the last ten miles of the ride.)

[schrader7032]

Here's where having the updated Doug Rinckes book would help with your troubleshooting. It lists the following for charge lamp not going out:

- brushes not running smoothly on commutator
- commutator greasy or oily
- regulator contacts dirty
- generator winding is faulty

I would certainly inspect the brushes. On the /5-on bikes, this can be a problem if the brushes don't slide easily in their holder, get too short, or get hung up by the small snail springs that are designed to keep the brushes tight up against the contacts.

I would also wonder about the regulator. There are several pages of tests for the regulator in the book.

[wheeler7664]

Kurt,
Thanks very much for the reply.
I found the book you mentioned and a bunch of other useful stuff by googling "Doug Rinckes."

But after reading more and starting to disassemble my bike, I think I'm going to drive the six hours from Atlanta over to Bench Mark. This problem, if not the others, is probably beyond my current ability to figure out and repair. I hope Vech and Richard will teach me a few things about the bike and how to work on it while I'm there!

And I may buy the Rinckes book while I'm there, too...

Thanks again!

[f11at125]

That's part of the title of a book by RICK JONES: "Classic Boxer Charging - Self Help for the Electrically Challenged." Unfortunately the last part of the title (at least on the one I have) is "BMW Twins 1970-1995". But if there is an edition of this book written for your bike, it's written for mechanics who are uncomfortable as soon as anything turns electric, for those of us who have to think to remember which one is a resistor and which one is a capacitor, but it isn't written in that condescending "Idiot's Guide" tone, and assumes you aren't a COMPLETE halfwit - just electrically numb. It has saved me from 2 GEN light incidents. The first was caused by a failed voltage regulator, the second by a dead alternator, and for each of these there was a linear, illustrated jump process ("ground the DF lead and check if the GEN light goes out - if it does, you need a new alternator"). Like I said, mine was written for the R75 I ride, but if there is another edition, or if you have a qualified mechanic who might have a copy ling around...

One caveat - if you are talking about riding that 6-hours, with your GEN light on, don't. At least not until you get the problem diagnosed. If it's the voltage regulator, and you jump it, you'll need to keep your RPMs below 3,000, which would make for a long, long ride. If it's your alternator, your bike will run for several hours off the battery. And then it won't.

Good luck - and I assume you were talking trailer, but if not, be sure to bring a cell phone, toothbrush and a credit card.

[f11at125]

When am I going to learn to just be patient and wait for the forum to load, and that I can't delete double-posts without bothering the mods? Maybe today.