Tuesday, January 7, 2014

Charging Problem

Yesterday evening was the monthly Airhead.org meeting at the local micro-brewery. Someone commented that this was some motorcycle group as there was only one bike parked out front. It was a wonderful ride out there (about 14 miles) and when I reached down to turn off the heated gear, I discovered that I never turned any of it on. You gotta love the barn-door windshield and fairing on the RT. It was about +12°F when I left the house. No problems with water in the gas but I have changed gas stations.

I noticed a problem when I started the bike to head home. With the ignition on and the engine not running, the GEN light should be lit in addition to the OIL pressure light. BMW has this weird wiring for the charging system where the GEN light is wired in series with the voltage regulator to the brushes and grounded through the rotor. If there is a break anywhere, no charging. Once the alternator is generating electricity, there is a second bridge of small diodes to convert the three phase AC output of the alternator to DC, route it back to the voltage regulator which is on the ground side of the GEN light. So the bulb is lit by the difference between battery voltage and the alternator output.

Hopefully, it's just a blown out bulb but it could be voltage regulator, brushes or the rotor. The lack of charging was verified by the digital voltmeter. No problem riding home as there was plenty of battery capacity even with the heated gear turned on. The battery voltage was still 12.2v after the trip home. Odd that BMW chose the indication of a problem was the indicator not being lit.

No opportunity for any troubleshooting as I'm on my way to Barrow for at least the rest of the week maybe into the beginning of next week. Another experiment, this post is being written on my iPhone during the flight. We'll see how it looks…

Update Tuesday afternoon - Like every other iPhone app I've tried that works with Blogger, Blogsy for the iPhone is garbage as evidenced by Martha's comment. I believe that it isn't that no one knows how to write software but Google keeps changing the way they do things.


10 comments:

Unknown said...

Richard:

I hope it's just a burnt out indicator light

In the old days with our old cars, we used to aim our lights at a blank wall, Let the engine idle as we turned on all our electrical plus high beams. If you revved the engine a bit and the lights went brighter then you knew your generator was Okay.

I am thinking that Barrow is warmer than Fairbanks, that's why you are going. You sent all the arctic air to the East

bob
Riding the Wet Coast

RichardM said...

Barrow is a little colder than Fairbanks at -10°F so that isn't the reason for the Barrow visit. There seem to be some network issues maybe stemming from the massive hardware update that I had to do last time.

That was one of my cues as the headlight brightness didn't really change with RPM.

redlegsrides said...

Hopefully its the idiot light. Then again, there's those upgrade charging kits for airheads that bolt right in, give you more power......

Martha said...

I clicked on your top photo and it took me to a selection of photos headed up with potatoes and eggs. That looks good, too. :^)

RichardM said...

Thank you for the comment. I went in and redid the photos as Blogsy for the iPhone didn't do a very good job with them. This was a disappointment as their iPad app is great.

RichardM said...

I'm hoping that it's the bulb but the brushes are also suspect as I've never had that part of the system apart. If it's the rotor than maybe it's time for an Enduralast alternator. 425 watts would be nice to have. But I can also just run off of the car battery for a while.

VStar Lady said...

You had me puzzled, not about the charging system, well okay about that too (from the un-mechanical here) but about your post ... until you replied to Martha. I was going to say, there doesn't seem to be a problem with the post - but you re-did it. It's a good thing (from both the mechanical and the technical sides - that you are 'handy.')

RichardM said...

I think that I've tried about ten different iPhone apps that claim to work with Blogger. Most do just fine with text but fail when it comes to pictures. The browsers don't work well with the javascript that Blogger uses on the "Compose" page even when trying to edit in html. Email pictures to post sort of works but you can't do any formatting. Blogsy on the iPad works great.

I'm actually looking forward to digging into the charging problem.

Trobairitz said...

Hopefully you get the charging issue worked out. Funny that you had no heated gear on and then the charging issue, you think it would occur after heavy use. Fingers crossed it is a simple fix of the indicator light.

Have fun in Barrow. Sounds a little chilly. We woke to 45 this morning - day two of rain. No complaints though.

RichardM said...

Hopefully it'll just be a burned out bulb. There is a mod where you can solder in a resistor parallel to the bulb so that charging will still occur with a burned out bulb.