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robmack


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Can't say that definitely because the poor condition of the battery will draw the terminal voltage of the alternator down. You need a load test on the battery.

When I got home I tried connecting the multimeter again but it would not start while connected. I let it sit while I went to eat dinner. Afterwards, I tried starting it with the meter connected and then it would start.
And now I'm reconsidering my declaration earlier that nothing is wrong with your Hall Effect Sensors. They might be acting up. Your description above is now pointing in that direction and the problem does not move with the swapped ICU.

http://k75retro.blogspot.ca/
    

kringb

kringb
Silver member
Silver member
@robmack wrote:Can't say that definitely because the poor condition of the battery will draw the terminal voltage of the alternator down.  You need a load test on the battery.
If I understand this right then you are saying, we can't judge the condition of the alternator with a bad battery connected. But we also can't yet say if the battery is bad without first doing a load test? There is a chance that this battery is good?





When I got home I tried connecting the multimeter again but it would not start while connected. I let it sit while I went to eat dinner. Afterwards, I tried starting it with the meter connected and then it would start. 
And now I'm reconsidering my declaration earlier that nothing is wrong with your Hall Effect Sensors.  They might be acting up.  Your description above is now pointing in that direction and the problem does not move with the swapped ICU.

I no longer trust any of the stalling and readings that I was getting when the meter was hooked up to pin 8/1 connector. It was making things happen that are not consistent with the way it behaves when it usually cuts out. It usually does not stall. It regains power within about 3 seconds. Also, there is no cooling down needed. it will often cut out once or twice in succession and then drive fine at the same speeds for the next few days or weeks. So, I am not taking into account the recent cutouts and bad running when the meter was connected. I think the meter caused those problems or exacerbated it.

That said, it may be loosing spark. I have not been able to prove otherwise. Is there any way to test for that while I am driving?



Last edited by kringb on Wed Mar 11, 2015 3:39 pm; edited 1 time in total

    

Holister

Holister
Life time member
Life time member
The problem is that you can't measure the charge voltage from the alternator until you have a properly charged battery. I only mentioned the alternator charging because that is one possible cause of why your battery is gone.

When you charge a battery you will get a surface charge which will dissipate over 12 to 24 hours. That's the 13 V you're reading. The next morning you say that comes down to 11.5 V. That is the true static charge of your battery. The static charge should be 12.5 V to around 13.0 V or more. If a battery can't hold a charge above 12.45 V it is no longer a servicable unit. You can do a load test but it will fail. EDIT: Batteries that can hold a charge above 12.45 V can fail a load test. They'r also not serviceable.

If you are unsure, get a battery shop to test. You'll probably find your Cold Cranking Amps on that bat will be around 100 CCA. The K100 engine requires a 360cca 28amp battery. I've seen 28amp batteries advertised for the K100 with only 280cca. This sort of batttery does not have the capacity to last. 30amp 380cca is a better choice.

Computer controlled engine systems are voltage critical. IMO you need to replace the battery before you do anything else otherwise you're wasting your time. At worst it could be that your battery is now occassionaly dipping below its ability to supply correct voltages for sensors and ECUs to perform and so they shut down. At best it will make it difficult to troubleshoot your electrical problem.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

charlie99

charlie99
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VIP
true indeed ...had to change my battery recently because of a non run situation

once changed all good ....so far (but in the mean time .....time to replace the regulator and the brushes that connect to the slip rings )

I have noted that a few of us (over time ) have had failures at approaching idle or backing off at least  as the alternator fails to keep charge on the battery ...the voltage drops and the electronics fails big time ...

I believe that the field current of the alternator  increases to compensate the low voltage ...which with a failing battery is unavailable to supply ...the bike dies


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OAnother poor soul with the intermittent stalling issue - Page 2 Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

kringb

kringb
Silver member
Silver member
I ordered a 30AH battery with 380cca today. I'll let you know how it goes. That will be a very happy, although anticlimactic, end to my troubles if it turns out to be a weak battery is the cause. I would have to make up a better reason for all my neighbors who have seen me toiling away at this problem. It would be too embarrassing to say that it was the battery.


__________________________________________________
85 k100rs | 78 xs650
    

Holister

Holister
Life time member
Life time member
Realistically, nothing is guaranteed but take hope from the fact that there is another K running nicely today because he installed a new battery.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

92KK 84WW Olaf

avatar
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Kaptain Holister wrote:The problem is that you can't measure the charge voltage from the alternator until you have a properly charged battery. I only mentioned the alternator charging because that is one possible cause of why your battery is gone.

When you charge a battery you will get a surface charge which will dissipate over 12 to 24 hours. That's the 13 V you're reading. The next morning you say that comes down to 11.5 V. That is the true static charge of your battery. The static charge should be 12.5 V to around 13.0 V or more. If a battery can't hold a charge above 12.45 V it is no longer a servicable unit. You can do a load test but it will fail. EDIT: Batteries that can hold a charge above 12.45 V can fail a load test. They'r also not serviceable.

If you are unsure, get a battery shop to test. You'll probably find your Cold Cranking Amps on that bat will be around 100 CCA. The K100 engine requires a 360cca 28amp battery. I've seen 28amp batteries advertised for the K100 with only 280cca. This sort of batttery does not have the capacity to last. 30amp 380cca is a better choice.

Computer controlled engine systems are voltage critical. IMO you need to replace the battery before you do anything else otherwise you're wasting your time. At worst it could be that your battery is now occassionaly dipping below its ability to supply correct voltages for sensors and ECUs to perform and so they shut down. At best it will make it difficult to troubleshoot your electrical problem.

This is extremely important. The Merc I had was extremely sensitive to battery voltage and a bad battery would cause all sorts of problems like this, ABS faults, electrical issues, running/performance issues, transmission issues, you name it. For what its worth I reckon if anyone gets electrical issues a battery replacement before doing anything is a wise move. Despite the age of the K being before this it was extremely advanced and is sensitive to battery voltage.

My LT failed just like above on a week away with my son. Before the trip the battery was out, tested and found to be fine with good voltage and a few weeks later on our first day away bike wouldn't start. Battery toast. Replacement battery was the cure.

Thing is, if any of your neighbours has a similar problem with their car/bike you can now send them on the right track. That's worth a good beer from each of them.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 40,490 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 42,640 miles.

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

kringb

kringb
Silver member
Silver member
While waiting for the new battery I decided to check the valves. The exhaust valves are all within range but one of the intake valves is tight. It measures somewhere between .13mm and .15mm. Probably closer to .15, .13 fits pretty loosely. I know this is not causing my cutout problem but does this mean that I need to get the shim replacement tool and fix it? Or is too tight on an intake valve less crucial than on exhaust?



Last edited by kringb on Sat Mar 14, 2015 9:37 pm; edited 1 time in total (Reason for editing : Added note on fit)


__________________________________________________
85 k100rs | 78 xs650
    

Holister

Holister
Life time member
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You're right. It's not likely to be the cause of your problem but valve clearance are better loose than tight. The advice I've found is too loose is ok... too tight is not. I'd re-shim and any others (particularly on the exhuast) if they're a little on the tight side as robmack said earlier,  just too be sure.

Read this post. The place to buy the tools is listed somewhere towards the end of the tread. He's the cheepest.
There's also some very good info from RickG.
https://www.k100-forum.com/t8864-exhaust-valves-how-bad-is-this

Look on youtube for Chris Harris. He has a short video on checking and replacing shims.
You can buy the shims individually pretty cheap.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

charlie99

charlie99
VIP
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if your doing only one or two,  you don't need the shim tool .......but it makes the job pretty easy if you have it


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OAnother poor soul with the intermittent stalling issue - Page 2 Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

kringb

kringb
Silver member
Silver member
I got the new battery in and the valves adjusted and am back on the road. It's too early to say if this will have any effect on the cutting out issue. But now that the battery is good I should be able to do an accurate test of the alternator/charging system.

Kaptain Holister had written:
Damaged alternator. The only way to test an alternator is to measure the charge voltage across the battery at >2000rpm. Should be 13.8 V or more. Its ability to get the bat up to 13 V doesn't really say anything about the alternator's ability.

So with the new battery in here is what my multimeter is reading. 
Engine off, the newly installed battery read 12.55 V.
Once the bike was started and warmed up then at idle it read 13.58 V. When I revved it over 2000 I initially saw the meter read 13.59 and then quickly it settled down at 13.55. I tried that a couple of times with same reading. When i returned it to idle it returns to 13.58 V.
After driving to work (~15miles) it read 12.85

From what Kaptain Holister wrote this seems low, right? Should I next test the voltage at the alternator? 







I purchased the Polepenhollow Valve Tool. It worked great, the price was reasonable and the service was excellent. The seller asked that I mention him in a forum post so here it is:


Details for purchasing the tools below

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2. “Clutch Pilot” - for the BMW 2 valve "K" engine.  $23.00, S/H included                                               
  
3. “Clutch Pilot” - for the BMW “R1100 Oil Head” engine. $23.00, S/H included
                              
TOOL DESCRIPTIONS  
1.     “Valve Adjusting Tools” for both K75 & K100 are 2 pieces made from 3/16”     
      Laser cut steel. Working contours are identical to factory tools. "Valve  
      Adjusting Tools" are new, steel, w/ instructions. 
“Valve Adjusting Tools” for BMW 2 valve "K" engines are $29, S/H included.
 
2.        “Clutch Pilot” for both K75 & K100 new, from steel, w/ instructions.
        “Clutch Pilot” for BMW 2 valve “K” engines are $23.00, S/H included.
 
 3.    “Clutch Pilot” for BMW R1100 Oil Head new, from steel, $23.00, S/H included

For Picture of Tools   
         go to Yahoo "Flickr":
 
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Or investigate the entire photo stream.
   
http://www.flickr.com/photos/41449418@N08/         
 
For a video to see the valve tools in use,
https://www.youtube.com/watch?v=yUxkv08XwH0
 
 
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Reply for shipping costs please.
 
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See attachments for pictures.
 
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“Pay Pal” accepted. Please apply “Pay Pal” to:  polepenhollow@yahoo.com
Parts will be shipped within 24 Hours of payment received, or “Pay Pal” is posted.
 
Thanks, Good Luck and Good Riding.
 
Kenneth Lively


__________________________________________________
85 k100rs | 78 xs650
    

Point-Seven-five

Point-Seven-five
Life time member
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Voltages look good.  Charging system should run at 13.5 to 13.8 volts.  12.85 volts indicates a fully charged battery.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

Holister

Holister
Life time member
Life time member
13.55 seems a bit low to me. A battery's optimal charging voltage is 13.8 to 14.4V. The voltage regulator has a range of 13.7 to 14.5V.

Try measuring the voltage at the alternator connector. If its any different to the charging voltage measured across the battery terminals then you could have a poor earth connection. If its still 13.55 you may have a problem with the alternator. The voltage regulator may just need adjusting

EDIT: Sorry, probably not adjustable. You'd need to replace. EME Part # BOALT-REG286 . They're pretty cheap. EME also have an adjustable regulator for an few extra dollars.



Last edited by Kaptain Holister on Sat Mar 21, 2015 6:12 pm; edited 1 time in total (Reason for editing : Correction)


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

RicK G

RicK G
admin
admin
So with the new battery in here is what my multimeter is reading. 
Engine off, the newly installed battery read 12.55 V.
Once the bike was started and warmed up then at idle it read 13.58 V. When I revved it over 2000 I initially saw the meter read 13.59 and then quickly it settled down at 13.55. I tried that a couple of times with same reading. When i returned it to idle it returns to 13.58 V.
After driving to work (~15miles) it read 12.85

12.55v is quite good and means a healthy battery. 13.58v at Idle is quite acceptable and probably a little higher than I would expect, 13.2 13.2v is more like what I would expect to see but that is probably just the idle being slightly higher than the 950rpm that is the accepted normal idling speed.  Only increasing to 13.58v at 2000rpm is totally non acceptable and to me means the alternator is in desperate need of an overhaul or that there is a very high load on the alternator when there should not be.
14.1 -14.2v is what I would expect to see at 2000rpm. With the headlights on all the time in the US then 14.1v at a minimum.
I have used the EME adjustable regulator and found that by adjusting it higher it was only compensating for problems elsewhere and would not really recommend using one unless you were doing a lot of night time riding where you are using extra lighting and then the best solution is to fit a higher output alternator like a 50Afrom a K1100 or a 60A from a K1200 which is not a straightforward fit as the 50A is.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

kringb

kringb
Silver member
Silver member
Tq
From the connector at the back of the alternator I am getting 13.75 V. At the battery, today, I am getting 13.45 V. Is that discrepancy abnormal? From these readings, is my next step to open the alternator and look inside?

Edit: those are the readings when the engine is revved over 2000.


__________________________________________________
85 k100rs | 78 xs650
    

kringb

kringb
Silver member
Silver member
After thinking about my last post I wanted to try to disconnect the alternator and measure from the prong. (Last time I measured from the back of the connector. So I gave it a try but now I am getting 0 reading from the alternator at any rpm. I then removed the regulator and the brushes are worn way past the service limit. The highest point on the tallest brush is just below the limit but it is just a corner. So they obviously need replacing. I don't like the coincidence that the output went to 0 just now as I am looking at it. But I quess all I can do now is put in new brushes and retest. From a quick search I saw brushes at 19.00 and the regulator that Kaptain H. linked to is just 29.00 and includes brushes. Unless someone has something bad to say about that regulator then it seems the way to go.



Last edited by kringb on Sun Mar 22, 2015 9:06 pm; edited 2 times in total (Reason for editing : Spelling)


__________________________________________________
85 k100rs | 78 xs650
    

charlie99

charlie99
VIP
VIP
the regulator - alternator will not develop any voltage when disconnected from the battery ...unless started with a battery attached
it relies on a couple of things ...1 the field voltage from the charge indicator lamp
2 the feedback of voltage from the battery - load to act as a reference .


in fact it is a known "do not do thing" with alternators to remove the battery  ...because there is no positive voltage  reference an alternator will try to ramp up its voltage until a load is accomplished ...usually killing the rectifier diodes in the process (at about 50 volts ) and all electronics attached at about 16 volts .... there is a modification for a lot of alternators  to change those diodes and use it as a welder  with 70 - 120 volts striking voltage

I have seen globes blow on an old ford when the battery terminal went high resistance and at change of beam ...high to low whilst at speed ..the alternator went crazy high volts .fortunately it was completely mechanical ignition system,

yes change the brushes at least

make sure that voltage drop that you have noted at running (13.75 at alternator 13.45 at battery )..is not a high resistance cable ...and limiting the amount of charge to the battery

it could be significantly higher at full load ....lights on etc

just some thoughts

good luck


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OAnother poor soul with the intermittent stalling issue - Page 2 Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

Holister

Holister
Life time member
Life time member
Worn brushes not making good contakt would probably account for the low charging voltage. Will be interesting to see. But the discrepancy between the voltage at the alternator and at the battery is most probably, as charlie says, resistance between the two... cable/connections etc. Deoxidising the alternator connector and the earth connecton on the GB and checking the cable for corrosion/damage would be a good idea.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
Silver member
Silver member
@charlie99 wrote:the regulator - alternator will not develop any voltage when disconnected from the battery ...unless started with a battery attached
it relies on a couple of things ...1 the field voltage from the charge indicator lamp
2 the feedback of voltage from the battery - load to act as a reference .


in fact it is a known "do not do thing" with alternators to remove the battery  ...because there is no positive voltage  reference an alternator will try to ramp up its voltage until a load is accomplished ...usually killing the rectifier diodes in the process (at about 50 volts ) and all electronics attached at about 16 volts .... there is a modification for a lot of alternators  to change those diodes and use it as a welder  with 70 - 120 volts striking voltage

That is good information to know. thanks. Hopefully I did not make things worse by trying to test the alternator without the battery. Maybe the weak brushes or regulator kept it from being able to get to 16 volts. 

I was thinking of opening up the alternator to check the slip rings but now I am thinking of leaving well enough alone and to just replace the regulator/brushes.


__________________________________________________
85 k100rs | 78 xs650
    

RicK G

RicK G
admin
admin
To be quite honest you probably have fried the diodes and most likely the regulator. Get a good used alternator or take it to an auto electrician and get it fixed.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

kringb

kringb
Silver member
Silver member
Damn, another lesson learned the hard way. 

I was very eager to get my bike going again so earlier today I ordered the regulator brush set. So now I am committed to going down the fix it road. When it arrives I'll try and see if I get any reading after installing it. If not, and if the diodes are all fried then I'll look into replacing those too. They are supposed to be cheap but finding the right ones will probably be a pain. Ugh.


__________________________________________________
85 k100rs | 78 xs650
    

RicK G

RicK G
admin
admin


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

Holister

Holister
Life time member
Life time member
@kringb wrote:...... So now I am committed to going down the fix it road. When it arrives I'll try and see if I get any reading after installing it. If not, and if the diodes are all fried then I'll look into replacing those too. They are supposed to be cheap but finding the right ones will probably be a pain. Ugh.
For what you'd pay for a regulator and a rectifier you could nearly buy a remanufactured 32 amp alt.
http://www.euromotoelectrics.com/category-s/767.htm

Have you tried re-testing the alternator since... with the connector back on?


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

charlie99

charlie99
VIP
VIP
yes retest ...before you do anything after replacing the regulator
getting into the diode pack is no easy job ...and removing them is quite an interesting experience to remove the rivets etc  that hold the diodes heatsink

but be prepared to undo the connections pretty quick if it all goes crazy

there might be a saving grace in that there was no reference voltages from the battery terminal ....well hope so

look into replacing that wire from the output of the alternator to battery as well ...there are upgrade versions available ...and reasonably priced

good luck


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OAnother poor soul with the intermittent stalling issue - Page 2 Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

kringb

kringb
Silver member
Silver member
Kaptain Holister wrote wrote:Have you tried re-testing the alternator since... with the connector back on?

I did, after reading RickG's post. I got 0 reading. I was too pissed at myself to write about it. I was mad that I blew my alternator and also mad that I had rushed out and ordered the regulator so quickly.


Charlie99 wrote wrote:but be prepared to undo the connections pretty quick if it all goes crazy

What should I be watching out for if all goes crazy? is there a chance that I could damage the new regulator if the diodes are fried? I really don't want that. Would be best to test the diodes first? At this point I should be expecting them to be fried shut, right?


__________________________________________________
85 k100rs | 78 xs650
    

charlie99

charlie99
VIP
VIP
first off measure the output connector  with the multi meter  on ohms 0-200

to the body of the alternator

then reverse the leads

bad would be any conduction from the output to the body

meaning that it would be putting ac (unrectified signal to the battery ) which will kill it

but more likely they have gone open circuit meaning they wont pass voltage at all

but reading the post above sounds like they have gone open circuit


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%OAnother poor soul with the intermittent stalling issue - Page 2 Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

Holister

Holister
Life time member
Life time member
@kringb wrote:..... and also mad that I had rushed out and ordered the regulator so quickly
You could try calling EME and cancelling the order or let them know you'll be returning it. Purchasing a secondhand alt off ebay will be much cheaper, but ask if its been checked.
A refurbished alt from EME would be another option.
Good luck with it.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
Silver member
Silver member
I measured the connector to body and got 0 conductivity from going either direction. I think now that it would be better to verify that the diodes are burnt open rather than waiting to try the new regulator. If I want to be able to return it I can't have used it.


__________________________________________________
85 k100rs | 78 xs650
    

Holister

Holister
Life time member
Life time member
That test does verify those diodes, connected thru the B+ terminal, are 'open' both ways and the rectifier is dud. There are other diodes connected thru the negative plate but you'll need to open the alt up to test those but imo it's not worth the trouble.
Just replace with a known good alt and you should be good to go if that's the road you're going down.

Which Alternator are you looking at buying?


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
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I've been fine with a 32 amp alternator so that is what I'll stick with. There are a lot to choose from but for various reasons this one looks good to me. I doubt many sellers are willing to test the diodes and the most you usually get are the claim that it was off a running bike. But my alternator survived over 100,000 miles before I tried to get clever so I assume they are pretty strong units.

http://tinyurl.com/olgefuu


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85 k100rs | 78 xs650
    

charlie99

charlie99
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take the second hand alternator .....and install the new regulator

then you have done all you can do to make it new again (except for replacing the bearings ) but if a low miles bike could be ok for a hundred thousand more ?

might be an idea to clean up the internal slip rings before installing the regulator in any case \

just what I think makes sense


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Holister

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@kringb wrote:I've been fine with a 32 amp alternator so that is what I'll stick with. There are a lot to choose from but for various reasons this one looks good to me......

http://tinyurl.com/olgefuu
32 amp is what you need. The 50 amp can be fitted apparently, with a little modification.

That one looks like a good clean unit.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
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Thanks for the vote of confidence, Kaptain. i went ahead and bought it. Once I get it in I will check back and report on the result.


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85 k100rs | 78 xs650
    

kringb

kringb
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The ebay alternator arrived. I checked the brushes and they looked good so i put it in and drove the bike to work this morning.

I measured the voltage and am getting some mixed readings. At home, after first starting the bike the reading at the battery terminals was low, somewhere around 12V. After warming up, approximately one minute then i was getting 13.76V at over 2000rpm. After that I drove to work. Once at work, (where i should be working to get money to pay for all these fixes) I was getting ready to post the results but decided to go out and get a reading at the alternator connector.

When i started the bike the readings were again very low. After warming up the voltage started to rise. It was somewhat erratic but generally increasing. At the alternator plug it got up to 14.2 while at the battery positive it was reading 13.85 (both were at high rpm). I shut it off at this point and did not watch to see if it would go higher. i thought that it would be safer to check in here.

Is it normal for an alternator to give varying readings like this, increasing as it warms up? I am also not feeling confident in my multimeter. It says that it was made in China so the quality should be good but you never know.


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85 k100rs | 78 xs650
    

92KK 84WW Olaf

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When you start a K you must run it to get the charge light to go out to get the alternator to kick start charging. If you simply start and let it tick over it runs down the battery. If you take the reading immediately after starting without revving it I imagine you will only get battery voltage which was the 12volt reading you got.

Clymer manual 'start the bike and let it reach normal operating temperature' or run for about 15 minutes riding.
Then stop and check battery terminal connections are good.
Start the engine again and run at 1,400 rpm.
You should read 13-14 volts at the battery terminals [not alternator terminals].
Turn on lights etc and it should remain 13-14 volts.

You seem to be in spec at 13.86 volts unless it was still rising fast.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 40,490 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 42,640 miles.

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

Holister

Holister
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@kringb wrote:......
When i started the bike the readings were again very low. After warming up the voltage started to rise. It was somewhat erratic but generally increasing. At the alternator plug it got up to 14.2 while at the battery positive it was reading 13.85 (both were at high rpm). I shut it off at this point and did not watch to see if it would go higher. i thought that it would be safer to check in here.
.......
As Olaf says it looks to be ok but you do need 13.8V minimum charging across the battery terminals. Higher is better.
You are losing nearly 0.4V between the alt and the bat. Not too much cause for alarm but as mentioned previously you need to make sure the earth connection on the gearbox is good and check the Battery cables, they can get damaged and corroded which adds to the resistance in the system and will lower the voltage. The connector on the alt needs to be clean and tight as well.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
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I didn't trust the multimeter that I was using this morning. After driving home from work I took another reading with the suspect meter. Again, the readings kept increasing I kept measuring as it slowly climbed to 14.26 at the battery before giving up and looking for an alternate meter. I have a few of these cheap meters. I found two other meters and they both agreed so I thnk the readings below are accurate.


With the engine fully warmed up and at fast idle  I get a reading of between 13.28 and 13.34 at the battery. With the engine off I am getting 12.49 at the battery.

I know, Kaptain Hollister, that you have said that it should be getting 13.8 minimum. But the manual says between 13 and 14. Maybe this is due to the headlight being on? 

I'm trying to verify this eBay alternator is ok before the return period ends. Thanks for the help.


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85 k100rs | 78 xs650
    

Point-Seven-five

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The more current the bike and battery are drawing from the alternator the lower the output voltage will be.  I may be wrong on the K bike, but I would expect the voltage to be close to but not hit 13.8 until the battery is almost charged.  The headlight load would probably keep the voltage from getting much over 14v.  I almost wonder if among other things, the headlight always on isn't to keep from overcharging the battery and boiling off the electrolyte.

I am basing this on my experience with other charging systems.  I could be wrong when it comes to what BMW designed.  They often seem to have their own ideas on how things should operate.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

Holister

Holister
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This will be my last post for a few days as I'm trying to get packed atm for two days on-the-road, leaving first light tomorrow morning. Rain is closing in so I'm going to have a nice slow ride in the wet.

13.85 is required to keep pace with the bike's load requirements and keep the battery charged. Anything below this and it will struggle >> battery will drain causing strain on the system ending up in damaged battery, burnt relay, overloaded starter motor and alternator.
Read back thru the thread to see what others have said... for example RickG says it should be 14.1V. I'm saying 13.85 is bare minimum. Trickle chargers will charge at a lower V but when the motor is running 12.85V is required. Turn your lights off while testing.

I'm concerned with the static charge your NEW bat has at 12.49V now. Is this straight after the motor is turned off? If so it should be much higher. Static charge (after the battery has rested for some time) should be no lower than 12.5V. A short while ago this was new and you reported 12.55V. Your battery needs to go on a charger.

One thing to consider is that there could be a parasitic drain on your battery (possibly a short in the wiring etc) which could be affecting the charging voltage also and draining your bat. Just a thought.

Adios Surprised-o:


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
  Another poor soul with the intermittent stalling issue - Page 2 Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

kringb

kringb
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Thanks Kaptain. Have a nice ride. If I ever get this thing sorted out then I have a trip of my own on the horizon.

There is no light switch on my bike but I can try unplugging the bulb and see how it reads.

Does anyone have any recommendations on how to find a parisitic drain? Or how to determine if there is one?


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85 k100rs | 78 xs650
    

robmack

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kringb

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Thanks Robmack. 

I am still trying to determine if this ebay alternator is a keeper or if I should try to send it back. The battery's static charge may be in question (even though it is new) and there may or may not be a parasitic drain on my voltage. Those I am looking into but I am mostly concerned with the alternator right now. So, last night I charged the battery with my battery tender and got it up to 13.3 volts. I do not know if the battery was fully charged. My tender has a light on it that should switch from "charging" to "storage" when the battery is fully charged. this morning it was still on "Charging". Does that make these readings below irrelevant until I get a fully charged battery?

Here is what the alternator readings were this morning after warming up the bike:

Headlight Disconnected, at 2000rpm: 13.71 volts at battery | 14.1 volts at alternator plug
Headlight Connected, at 2000rpm: 13.54 volts at battery | 13.8 volts at alternator

From these readings, can the alternator be ruled definitely as bad? Or could the battery or something else still be causing the low readings? From PointSevenFive's post it sounds to me like the voltage would increase once the battery was fully charged. Is that correct? How could I tell when a battery is fully charged except by watching the light on the tender?

thanks.


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85 k100rs | 78 xs650
    

92KK 84WW Olaf

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A thought......how confident are you of the accuracy of the meter taking the readings? Its just that the battery is showing low and the alternator readings are also showing low. My thought is try another meter on the fully charged battery and see what you get. Both the 12.49/12.55 and 13.54 seem low by about .30 volts but the relationship between the two readings seems about right.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 40,490 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 42,640 miles.

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

kringb

kringb
Silver member
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I've got three meters. They are all free giveaways from Harbor Freight. Two red ones give identical readings. One Yellow one gives readings that are slightly higher, roughly .05 Volts higher. Because I am an optimist at heart I have been giving the readings from the yellow one. They could all be off but that seems doubtful. Still, I will try to to borrow a better one and see what it reads.

I understand that these test are best taken when the battery is fully charged. How can you tell when the battery is fully charged? By the voltage? This morning it read 13.3 after taking it off the charger. On the charger it read 14.01. Was that fully charged?


If I am understanding correctly then any load on the system lowers the voltage reading at the battery. What would be the best way to test if there is an unnatural load on my system? Could I unplug all the fuses and see if that causes a jump in voltage? I am hesitant to say the alternator is bad because it is giving basically the same readings as my old one. Sure they could both be bad but I never trust coincidences.



Last edited by kringb on Wed Apr 01, 2015 3:45 pm; edited 1 time in total (Reason for editing : added last paragraph question)


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85 k100rs | 78 xs650
    

Point-Seven-five

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Sounds like it's fully charged.  Usually  battery will read about 13.8 when it first comes off the charger.  That is the result of what is referred to as a "surface" charge caused by electrons loosely bonding to the surface of the plates.  This will usually dissipate over a short while allowing the true charge to be measured.

Rule of thumb for battery charge is 12.8v is fully charged and 11.8 is no charge.  Every .1v drop in voltage is a loss of about 10% of the capacity.  Any time a battery is left sitting with less than a full charge for more than a day or so will result in chemical damage to the plates inside, and a corresponding loss in it's capacity. 

The only way to truly test  battery is to "load" test it by drawing a fairly heavy current while measuring the battery voltage.  The higher the voltage under load, the better the battery is.  The best test is to measure the battery voltage while the battery is running the starter motor.  Haven't run a start load test in years, and can't remember what you should see.  Might want to do some research on the interweb.  10.0v sounds about right, but I would want to confirm it.

If it's spinning the starter easily, and you can get 30-40 seconds of cranking time out of it, I would think it's OK.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

kringb

kringb
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To robmack's suggestion: I borrowed my neighbor's multimeter, which is very good one (a Fluke industrial grade). It measured about .03V  higher than the one I had been using. So that doesn't change the situation by much.

To Point-Seven-Five:  Thanks. So my battery is getting to fully charged I will leave it disconnected overnight and try to see the static charge. I will also try the starter load test and see what I get.

From Rick G's post wrote:12.55v is quite good and means a healthy battery. 13.58v at Idle is quite acceptable and probably a little higher than I would expect, 13.2 13.2v is more like what I would expect to see but that is probably just the idle being slightly higher than the 950rpm that is the accepted normal idling speed.  Only increasing to 13.58v at 2000rpm is totally non acceptable and to me means the alternator is in desperate need of an overhaul or that there is a very high load on the alternator when there should not be.
14.1 -14.2v is what I would expect to see at 2000rpm. With the headlights on all the time in the US then 14.1v at a minimum.

I'm not getting anywhere near the fast idle charging that you are saying is needed. So, as you say, either the alternator needs an overhaul or there is a very high load on the alternator when there should not be.

How can I determine if there is a high load on the alternator when there should not be?


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85 k100rs | 78 xs650
    

Point-Seven-five

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I am guessing that the running load on the alternator is around 14Amps.  That is about 6 for the headlight, 4 for the side lamps, 1 for the tail light, 1 for the instrument lights and 2 for the electronics. 

With the alternator light out the electrical system should be running at idle on at least 12.8 and more likely 13 or more volts on the battery terminals.  Anything less than 12.8 would indicate the the bike is running on the battery and not the alternator.  The voltage won't remain steady and will slowly drop all the while the engine runs as the battery is drawn down.


__________________________________________________
Present:
1994 K75RT
1991 K100RS
1988 K100RS SE

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

RicK G

RicK G
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I doubt very much that there is a load there that is unaccounted for, the alternator should charge the battery at about 14.1v at or over 2000rpm regardless of the state of charge of the battery because when the battery is low the battery voltage is low so the difference in voltage is higher than with a well charged battery so the charge rate is higher.
Have you taken the regulator/brush holder out and inspected the brushes. an educated guess here says that the brushes will be in much the same state as Fission Mailed's  that he posted a pic of in another thread.


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"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

kringb

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The brushes on this alternator are still ok. My caliper measures in inches and the 5mm limit equals .197" . The lowest spot on the concave of the shortest brush measures about .230".

I'm stumped. I could try to do an amperage test. But I am not sure how. If you remember, my original problem was the fuel injectors shutting off at high rpm, often when going up a slight incline. I am still thinking that this may all be related.

Or should I send this alternator back to the seller and tell him it's a dud?

Edit: just to add that at idle it is measuring at about 13.2 at the battery. It is at 2000rpm where the voltage is low. Does that point to any particular part of the alternator that is failing?


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85 k100rs | 78 xs650
    

RicK G

RicK G
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I don't believe the battery or alternator is the cause of the original problem that you are chasing. I have read the thread from the start and don't believe that the intermittent nature of the cutting out is at all connected with a slightly low battery voltage.
We should be going back to real basics here.
The firing of the injectors and the tacho are solely governed by the 2-3 part of the ignition system. The injectors cut out and the tacho falters at the same time.
Have you inspected the Hall sensors or even removed the cover. The Hall sensors are prone to giving problems of complete cut out when hot but nothing to say that is the only fault they are capable of, after all they are electrical components and as such can and will do all sorts of strange things.
There is a section on testing them in the portal page but what I am now thinking is that if the physical mounting is not tight then all of the things mentioned can happen or even if they are just failing in a different way to the usual way they die.
Keep the battery charged and keep the alternator connected and check out the Hall sensors. They were only ruled out because it was not the typical problem.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

kringb

kringb
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Silver member
I have been waiting to get back to the original problem too but now I have this alternator that I bought off eBay. I need to make a decision to keep it or return it and try something else. Probably a rebuilt one.

Could you give me your opinion? after driving to work the battery measured 13.2 (engine off). So it is charging. But is it going to wear out my battery or is it worth keeping?

Thanks.


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85 k100rs | 78 xs650
    

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