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wolds
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VBMWMO #8011
Joined: 11/08/2010
Posts: 47

Hello all. Well after 8-1/2 months of work my R60/6 is done:). Start-up went as planned and I've got a basic tune / sync on the carbs. Problem is I have a charge indicator bulb that won't go out. Here's what I've done to troubleshoot. I jumped out the rotor per the manual and put a DVM across the battery. Switched on the ignition and the indicator was not illuminated. Started the bike and indicator was still not lit. Brought the RPM's up to 2-2.5K expecting to see the voltmeter rise from nominal 13.0V battery output. Voltage didn't budge. So I went back through the wiring to make sure things are right, which I believe they are. Measured the phases of the stator across each leg got about 1 ohm on each leg (within tolerance). Measured across the slip rings and got 4.3 ohms (which is low), should be about 6.7vdc. Any thoughts and where I should go from here? Thanks, Warren

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2007 BMW R1200RT
1983 Porsche 911SC cab RoW
1979 Yamaha XS650 Special II
1976 BMW R60/6

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
Posts: 4671
I'm not sure...the light

I'm not sure...the light won't go out or won't come on?? If the light never illuminates, you won't get any charging. It's important to make sure the bulb is at least good. Rick Jones' book (which you should consider getting) on boxer charging says to remove the front cover (after disconnecting the battery lead, then reconnect when the cover is off), and remove the wire from terminal DF on the alternator. Then with ignition on, touch this wire to ground...light should come on. If not, you need to pursue that.

I don't understand your rotor resistance readings. A /6 should have about 3.4 ohms across the slip rings, with a piece of paper under the brushes.

After that, you might need to check the voltage regulator. All of this assumes a good healthy battery...sometimes that creates its own problems.

Check out Snowbum's section on all of this:

http://bmwmotorcycletech.info/trbleshootALT.htm

One of the better wiring diagrams is here:

http://www.stephenbottcher.net/BMW/misc/ChargingSystem.jpg

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

wolds
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VBMWMO #8011
Joined: 11/08/2010
Posts: 47
charge sys

hello Kurt, That was a typo on my part RE slip ring resistance, I meant 6.7ohm's not 6.7vdc. According to my Haynes book that's what they call for + or - 10%. I measured 4.3ohm's which is below the low limit. The charge indicator was on till I un-plugged the relay and put the jumper in. According to the book, no light means bad relay but that doesn't explain the absence of a voltage rise with the relay jumpered out. Warren

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2007 BMW R1200RT
1983 Porsche 911SC cab RoW
1979 Yamaha XS650 Special II
1976 BMW R60/6

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
Posts: 4671
By relay, I think you're

By relay, I think you're speaking of the voltage relay. If the relay is bypassed as Snowbum shows on the previous link, and the voltage doesn't rise when RPMs go up, then the alternator is basically not working. If it were, the voltage would rise quite quickly to the 15v+ levels.

I think the most typical problem ends up being the rotor. It could be going open when running. You measured a lower resistance than is nominal, so under operation, it might not be working correctly.

I just read something that Snowbum posted on the Airheads Airlist which he said was a way of dealing with intermittent rotors. He said:

"I may use a test lamp between the battery + and the alternator brush holder terminal Df
(Df wire pulled off). I don't need an ohmmeter to tell me what the rotor and brushes
condition are,...and the advantage of the lamp method is, in addition to no meter being
needed, that this method will 100% turn on the alternator AND almost always 'show up' that
nasty situation when a rotor is acting-up only at some rpm, as opposed to engine not
rotating. Many a digital meter gets confused when trying to measure alternator output
under that kind of intermittency."

If the rotor is bad, Rick Jones can either rewind yours or sell you a rewound rotor after you send in your core.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

wolds
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VBMWMO #8011
Joined: 11/08/2010
Posts: 47
kurt, yes I'm talking voltage

kurt, yes I'm talking voltage relay. Thanks for the info. Warren

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2007 BMW R1200RT
1983 Porsche 911SC cab RoW
1979 Yamaha XS650 Special II
1976 BMW R60/6

kenrcruise
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VBMWMO #7965
Joined: 04/04/2011
Posts: 17
R60/6 charging

This is for Warren Wolds (#8011). I also have an R60/6 (1975). My generator light stays on and won't go off when the bike is running. Admittedly this is about 2 weeks after first startup after rebuild, with a new rotor. I plan to check the brushes.

How did you do with your R60/6 charging system once you got to work on it?

I am hoping to take mine on a rally in two weeks, and give it a full break-in (new pistons, rings). It has not run in 10 years.

Regards,

Ken Cruise (#7965)

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Ken Cruise

wolds
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Joined: 11/08/2010
Posts: 47
Ken, So it's been awhile

Ken,

So it's been awhile since I was sorting out my charge issue. Ultimately I put a new VR in and my issue was resolved. Typically the gen light will come on when the rpm drops below about 900. Other then that I'm getting 14+ volts when the rpm rises above 1500 or so. Not sure if this is an answer to your question or not. P.S., I'm not on this site very often and just happened to stumble on your post. Hope you were able to sort your issue out. There are many knowledgable enthusiasts on this site for support. PM me if you like at olds.warren@gmail.com

Warren

__________________

2007 BMW R1200RT
1983 Porsche 911SC cab RoW
1979 Yamaha XS650 Special II
1976 BMW R60/6

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