The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: msbuck on June 07, 2010, 04:44:24 PM
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AARGH!!!!
OK, now that I've got that out of my system...
When I took the Precision Maneuvering Class, all that slow riding with my lights on took it's toll. Of course, by noon my bike quit starting on it's own. I remembered that I should have disconnected the headlight, etc. Graham took care of that for me when we took our lunch break, but we still had to bump start the bike every time out.
We checked the charging system after we got it back home. The generator light was being very sporadic.
1.) Switch on, light off, hit starter, light came on, would go off around 1200rpm.
2.) Switch on, light on, engine running, light would not go off.
3.) Switch on, light on, engine running, light would go off around 2500rpm.
We checked the charging and had only about 12.8 volts charging maximum. We checked the brushes. They were worn, so we replaced them. Now, I have never soldered anything before and this was not a pretty job (to say the least!). But we got everything put back together and checked things out again.
NOW the Gen light comes on very brightly and STAYS ON. Sigh...
Checked the charging and we get NO charging, just the same voltage consistently throughout the rev range.
We checked the rotor and got a good reading. We're just stumped because before we replaced the brushes, at least we were getting SOME charging. We are concerned about
1. my soldering job - although it's ugly, it does seem to be a good connection. We checked continuity. Although some solder did wick up the copper wire - does this really matter?
2. reinstalling the brush holder. I'm fairly confident we put in the bushing/insulating washers correctly, but we didn't actually check this BEFORE we took it apart.
So I've done some searching both here on the forum and on the web. I've found lots of info on bad rotors (no light at all) - but nothing to tell me what it means when the Gen light stays on all the time (except no charging). What do I check next?
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The charging system guide from Motorrad Elektrik says that a stator issue will cause the light to come on bright .
To check the stator windings, remove the three wires from the stator case, these are the output wires, place a multimeter on one of the terminals with the meter set to the ohms scale, touch the other lead to one of the other terminals, you should get around .6 ohms, touch the lead to the remaining terminal, you should get the same reading .
Not that you did anything wrong, but if you didn't have this problem before working on the brushes, I would go back and check your work again .
The placement of the fiber insulating washers is important .
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The placement of the fiber insulating washers is important .
So can you tell me how they go? I have put them inside the housing. We can't find any pictures, descriptions anywhere of the placement of these.
Basically I installed... brush holder onto housing. Outside of housing I put a washer and nut. (I think this just installs the spade connector.) Inside of the housing, on left (looking from backside through stator wires) I put bushing, insulator, wave washer, nut. On the right I put insulator, wave washer, nut. Now we're wondering if the insulator goes between the brush holder and the housing on the outside?
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Going on the photo in the charging system guide, there is an insulating washer between the stator case and the brush holder .
I think that's where your problem, with out the insulating washers between the stator case and brush holder, the excitation voltage from the voltage regulator to the rotor, is going straight to a ground, causing the "GEN' light to come on brightly and never go out .
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I replaced the brushes on my R90 this winter and had the brush spring slip down the side of the brush. I did not find this until I started the bike and the Gen light stay on. Double check the brush spring are setting on top of the brushes.
Don
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>:( Moved the insulators and no change...
We've checked the stator and it checks out good. I guess tomorrow we test the diode board and go from there.
Another question about my brush replacement. The new brushes did not have any insulating sleeve around the cooper wire. I did not read snowbum's article (slap head) until after I had soldered the brushes. I did not move the old sleeves to the new wires, so they are bare copper wires. Does this matter?
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I did not move the old sleeves to the new wires, so they are bare copper wires.Does this matter?
That could very well be the problem. But I don't know, for sure.
Here is a picture of mine, if it helps with the washers and stuff:
click for REALLY big
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F113069338%2Flarge.jpg&hash=6d9afd572db48f7f83dd550f9481a5fa6f3c70fe) (http://www.pbase.com/tomfarr/image/113069338/original)
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Thanks for the picture, Rob!
Both Graham and I have been stewing over this all night. Now what we've decided...I've put the insulated washers on each bolt, both the positive and the ground. We were thinking that the two insulated washer should go only on the positive side, one in the front between the housing/holder and on the back between the housing/wave washer. I can clearly see from your picture that there is not an insulated washer on the ground side (at least in the front.)
We were planning on taking Graham's front cover off this morning to see how his was set-up, but with your picture that might not be necessary. Let's try this one more time - fingers crossed. please! ::)
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;D Hallelujah! Both insulator washers go on the DF side- one on each side of the stator housing. Thanks guys for all the help.
Now I have another problem....transmission vent bolt - stripped the threads in the case. :'(
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Yes I moved the insulation on to my new brushes. Also don't trim the braided copper wire to the brush. The brushes needs the slack so that as they wear they can pull the wire farther from your solder connection.
Probably stating the obvious but....if you have mucked this up then just go buy another set of brushes. They are cheap compared to getting towed off the road.
Good luck Aïda.
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...Now I have another problem....transmission vent bolt - stripped the threads in the case. :'(
The one on top of the final drive case? I'd be inclined to clean the vent bolt and the case r-e-a-l-l-y well and JB Weld that puppy back in place. No kidding. That's what I'd do. Honest. Anything else is gonna get costly, I'm thinking.
Monte
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Monte - what about the negative battery wire? That's where we disconnect to be able to remove the front cover.
Hmmmm....got me thinking here anyway. Thanks.
Semper - the insulated sleeve doesn't seem to make a difference. It's working fine now, just had the insulator washers in the wrong place. We checked the charging and I'm getting the full 14 volts at charge. Whew! I'm glad I didn't have to start all over.
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...Now I have another problem....transmission vent bolt - stripped the threads in the case. :'(
The one on top of the final drive case? I'd be inclined to clean the vent bolt and the case r-e-a-l-l-y well and JB Weld that puppy back in place. No kidding. That's what I'd do. Honest. Anything else is gonna get costly, I'm thinking.
Monte
And run a longer ground wire to some other location? I've been meaning to do that myself one of these days.
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If you change the battery ground connection, just make sure the cable or wire is heavy enough to handle the electrical load of the starter, the starter is grounded to the engine case through physical contact of the metal case of the starter touching the engine case .
The starter draws 150-200 amps when operating .
Any undersized connection would most likely melt under the load .
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Oops, Aïda. I was thinking of the vent bolt on top of the final drive case.
Another thought... careful. Perhaps tap the hole for an SAE bolt just slightly larger than the OEM. Use some heavy grease on the tap and you'll catch the chips. Thread a little, back out, clean and re-grease, thread a little more...
A short bolt could be gun drilled for the vent hole.
I often get in trouble when I get to thankin' too mucho. ;)
Monte
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BTW, the stripped threads are on Graham's bike ('81 R100) - and he was doing me a favor. [smiley=sad.gif]
Ok, so we moved the battery negative cable to the rear bolt that attaches the coil. The cable was just exactly the right length to reach. Then he cleaned up the threads, used a little aluminum foil to get the bolt started and then slithered a little JBWeld on the outside washers/bolt head to hold it all together. It looks ok and seems to work. We'll see...
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Ick! That sounds like a nasty bodge...
Eventually the transmission will need to come out so you can either re-tap for a size larger, or attempt a heli-coil fix, which I hear can be tricky because of the limited amount of material and whatever is right behind it on the inside.
Poor Graham... trying to help someone out...
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Another save by JB Weld! [smiley=thumbsup.gif]
Shoot, I'll bet it's no more ghetto than duct tape on a seat. Doubt anyone will ever notice it. Ride on.
[smiley=clap.gif]Monte
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Ick!That sounds like a nasty bodge...
Yeah, that's how Graham feels about it as well. At least the bike is road worthy at this point. You're right, when the transmission has to come out for something else, he'll probably take care of it.
He just likes things to be right. Shame on me for not taking notice of those little washers... :(
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If I don't take pictures when I take things apart, I at least draw pictures and take notes.
shame Shame SHAME! ;)
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First off, don't ever touch that hollow breather bolt - disconnect the negative lead at the battery instead!
Secondly, the battery cable can be moved to one of the trans cover bolts a few inches to the left. You'll need a long hollow washer or a stack of them and a longer bolt to attach it. It's a good idea for the negative lead to connect to the engine because the path from the starter to ground needs to be as short and direct as possible.
I once 'fixed' those tranny cover threads by crafting a metal piece to look like that black plastic spacer the speedo cable fits into. Instead of a slot, I drilled and tapped the spacer to accept the breather bolt. Works great!
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It's amazing what you can do with a metal lathe, isn't it!
A friend made this cap for me, since I use my GPSr for a speedometer, now:
The Vapor (instrument) users here might want to consider one of these.
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I want one of those. If I had the specs my buddy at work could make it.
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I want one of those. If I had the specs my buddy at work could make it.
Just take him the black plastic piece.
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...The Vapor (instrument) users here might want to consider one of these.
Sweet bit of machinist bling there. My tach cable hole is filled with a rubber bung plug; size matched and installed with a deft touch o' the mallet.[smiley=smash.gif] No JB Weld required...
Monte
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This is where I got the idea, from Stephen Bottcher's GS' "Ultra Vent":
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F113057943%2Fmedium.jpg&hash=f1b71ecd4db970710adf1e343ff4bfdb7d499969)
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F113057947%2Fmedium.jpg&hash=25fc22629b6e5f53b5837dd49073f8ea16b9410f)
http://www.stephenbottcher.net/BMW/R100ST_2.htm#gearbox
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Rob, does your plug extend as far down in the hole as the black plastic one? And do you have a bolt there at all, or is your plug just a solid cylinder? I'm wondering about how yours is vented.
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Mine is the same dimension, inside the transmission case, as the black plastic.
I had the machinist (an airhead guy) cut a slot on one side to accept and trap the original vent screw, which is still my vent.
Stephen had his vented out the top so he could put a hose on it and run it up under his fuel tank.
He also created a similar vent for his final drive. This is all for deep-water crossings.
http://www.stephenbottcher.net/photos/TAT2007/29/DSCF2909.JPG