The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: vontresc on August 04, 2013, 10:57:43 AM
-
So I was riding home last night when the bike died. Turns out that the battery was dead. I'm figuring that I was running off of the battery and that I'm not charging the system. The weird thing is that I did not see the generator light come on.
Any suggestions as to what may have failed? Generator diode board something else? I hate electrical troubleshooting so some tips on where to start would be greatly appreciated.
-
Does the 'GEN' light come on when the key is in the run or on position ??
An open rotor, or the 'GEN' light circuit may be open as well .
Need todo a bit of troubleshooting on these circuits .
-
Easy things first!
Check the GEN lamp for good/bad.
Charge the battery. Start the engine and bring the revs up to 3500-4000 rpm. Using a VOM, check charging volts at the battery.
Do that "free" stuff, then report back in with results. We can then offer suggestions to get you fixed up and rolling again. [smiley=thumbup.gif]
-
When my voltage regulator failed such that it would not allow any charging to reach the battery, my generator light did not come on. Test it by bypassing the regulator -- unplug it and use a jumper wire. Details on Snowbum's page.
-
Believe it or not, if the Gen light bulb is burned out, your battery will not be charged by the alternator. It is a design feature of the Bosch Alternator system.
Good luck.
-
Good thing to know!!!
Thanks!
-
It is a design feature of the Bosch Alternator system
AND old MG Lucas systems... ::)
I've had two Airheads with rotors that opened up...
-
No response from Mister Vontresc since his original post of 04 August. Guess he got it sorted 'cause we're just talking to ourselves. Good talk,yes, but it would be nice to get some sorta response as such. ::)
-
No response from Mister Vontresc since his original post of 04 August. Guess he got it sorted 'cause we're just talking to ourselves. Good talk,yes, but it would be nice to get some sorta response as such.
Closed threads are happy threads. But on a positive note, at least fbenach learned of the gen light woes (maybe he too can be praised by Ausherman one day).
AND old MG Lucas systems...
There's a reason they call them "the prince of darkness" ;D
-
OK, Luca... Are you on Boxerworks, too? ::)
-
OK, Luca... Are you on Boxerworks, too?
nope, just R65.org. I remember you posting about the Ausherman praise you got.
I was on VN750.com as bazooka_luca and now I'm on Miata.net as 650Boxer_Twin
Gotta say, this is the best forum I've ever visited.
-
Sorry, I've been stupidly busy the last week and a half. I finally got to it this afternoon.
So the bulb is ok (Thanks to the diagnosis from Snowbum). I tried jumping the VR, but got no charging light.
I only got about 1.5 volts when I measured the voltage at the gen (B+ on the Diode Board to D- on the alternator)
I did pull the brushes, and they are pretty worn, and in the process of playing with them I managed to break the wire at the solder joint. Gonna have to redo that anyway, so I'll sto by the local Beemer shop and pick up a new set of brushes (77+k miles on the bike so it's probably time anyway.
I'll report back when the alt is back together
Pete
-
While you have the brushes out check continuity on the rotor...
-
[size=18]+[/size] [smiley=thumbup.gif]
While you have the brushes out check continuity on the rotor...
-
Love it!
The knowledge just keeps on coming...
I'm like a sponge, just soaking it all in, it's amazing how much you can pick up, a big thank you to all the "sage's" on here.
Cheers
Chris
-
Yo, Chris...
Here in Texas, a sage is a desert shrub. Will set purple blossoms when it rains. "Bring me a shrubbery."
And what's rain?
-
<snip to the punchline> "Bring me a shrubbery."
Ni.
Ni.
http://www.youtube.com/watch?v=QTQfGd3G6dg&list=TLc4FfWFSsTZ4
LMAO
-
Rain?
It's what makes our fair isle so green...
And when it rains we work in our garages on our bikes :)
-
And when it rains we work in our garages on our bikes
Now I finally understand why I haven't adjusted my throttle cable slack or replaced my neutral switch, and it's not my laziness!
-
While you have the brushes out check continuity on the rotor...
Well when I first checked the rotor seemed to be OK. Alas, when I got the new brushes soldered in, I rechecked the rotor, and nothing. Looks like a bad rotor was the culprit after all.
Next question. The $450 genuine NOS part is out of the question. What aftermarket rotor replacement would you suggest?
-
Motorrad Elektrik and Euro Motoelectrics have after market rotors for around $100-120 .
http://www.motoelekt.com/charging.htm
http://www.euromotoelectrics.com/product-p/boalt-rotor642.htm
If you don't have one, you need to get an alternator rotor removal tool as well, it's around $5-6, just a hardened bolt with a few threads removed, a non-hardened bolt won't work and may get stuck in the rotor if it bends .
-
Contact Rick Jones at MotorradElektrik - they have remanufactured units for under $100 and they also have new (but not BMW) rotors that are warranteed to fit/work in the airheads for under $150. Go to this page and scroll down toward the bottom:
http://www.motoelekt.com/charging.htm
-
Thanks for your help. I ended up ordering a new rotor from EME. Got the bike up and running in no time.
In the mean time I just crossed over 77,777 miles on the bike.
-
Success all around and I keep learning things too or else trying to remember what you guys said! So bookmark another R65 forum page!!!
Thanks!