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1Back to top Go down   K100 First ride...then first push Empty K100 First ride...then first push Tue Sep 07, 2021 10:43 am

BespokeVillainy

BespokeVillainy
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I covered to this point on my original thread but since it will now start and run I will think it may be an unrelated issue.
85 K100 purchased a couple weeks ago as a non runner.
I replaced the ICU, plug wires, and plugs and the bikes fires immediately on cold start.  It warms up, surges RPMs, won't idle, and dies.  On warm restart attempts it behaves almost as if I'm back to square one: short cycles of the starter spinning, plenty of flow into and out of the tank . Suggestions made to check the fuel pressure regulator, vacuum pipe to it, as well as making sure the previous owner replaced the temp sensor with the correct part and didn't use sealant tape.
I'm also going to go through all connections including ICU and ECU with contact cleaner and dielectric grease.
Any other suggestions welcomed.
I did make it almost around the block before I found out these boots were made for pushing.  Cheers to that!!

    

BespokeVillainy

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New fuel pressure regulator, and it's vacuum hose is good.  There is good ground at temp sender and the PO stated confidence in it being the right one.  
I hooked up a test light to 12v+ and  started the bike.  I inserted the test light probe into the red/blue and red/black connectors while running to watch the ground signal.  That ground signal was definitely dropping away and causing the bike to die.
The coils, plugs, plug wires and ICU have been replaced and doing so has the bike cold starting great but dying and losing the ignition ground signal when it warms up.

    

MartinW

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The HES can fail when heated up. Probably worth checking out.
Regards Martin.


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K75s Hybrid
    

BespokeVillainy

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It's been replaced in an attempt to get it running by PO.  Also, does the Hall sensor have any bearing on starting?  I thought at starting RPM it wasn't in the loop?

    

MartinW

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You stated that it starts fine when cold but plays up once it warms up. "The coils, plugs, plug wires and ICU have been replaced and doing so has the bike cold starting great but dying and losing the ignition ground signal when it warms up."  It's worth rechecking.
Regards Martin.


__________________________________________________
K75s Hybrid
    

BespokeVillainy

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Now that I am in the "warm but won't restart" condition and know that I'm losing ignition signal, I tested ICU connector wires 9&14 and am getting full 12v while the starter is spinning.  The troubleshooting guide says it should be in the 1.5-4v range.

I get the same voltage using the old ICU.  What is responsible for dropping that voltage down?

    

Laitch

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@BespokeVillainy wrote:Also, does the Hall sensor have any bearing on starting?  I thought at starting RPM it wasn't in the loop?
If the Hall sensors during cranking or running are not outputting an engine speed (TD) signal to the ignition control unit, or the ignition control unit can’t interpret it because it is faulty, the spark plugs won’t fire correctly and fuel injector relay function will also be affected.


__________________________________________________
1995 K75 81,000 miles
K100 First ride...then first push Usa-lo10
    

MartinW

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I'd say that your problem is heat related. I'd try heating various components with a hot air gun and see what readings change. I've also resorted to packing crushed ice around components to confirm that the component is overheating.
Regards Martin.


__________________________________________________
K75s Hybrid
    

BespokeVillainy

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Going to try and track down an LED to test the sensor

    

10Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Tue Sep 07, 2021 4:05 pm

Point-Seven-five

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+1 on cooling the various electronic components when the engine is warm. Instead of the crushed ice, you can also use a freeze spray that comes in an aeresol can.

https://www.crcindustries.com/products/freeze-spray-10-wt-oz-14086.html


__________________________________________________
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
    

11Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Tue Sep 07, 2021 4:14 pm

BespokeVillainy

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So I just pulled the Hall and noted a piece of what feels like old gasket sealer off of the ring and you could see what looks like bK100 First ride...then first push Img_2013
K100 First ride...then first push Img_2011
K100 First ride...then first push Img_2012 urnishing.  The Hall sensor looked fine.

    

12Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Tue Sep 07, 2021 4:36 pm

BespokeVillainy

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I have 20ma 12V LEDs coming tomorrow.  I'll run the hall test cold and then heat it with a hair dryer and see if they fail.

    

13Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Wed Sep 08, 2021 5:54 am

Dai

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Looks like your 'bit of old gasket sealer' has done a good job of scoring and marking the rotor. Whatever it is, it shouldn't be in there and is possibly the cause of your misfire by getting bits of itself jammed in the hall sensors and then knocked out again as the hole comes by.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

14Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Fri Sep 10, 2021 12:54 am

daveyson

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@BespokeVillainy wrote:Now that I am in the "warm but won't restart" condition and know that I'm losing ignition signal, I tested ICU connector wires 9&14 and am getting full 12v while the starter is spinning.  The troubleshooting guide says it should be in the 1.5-4v range.

I get the same voltage using the old ICU.  What is responsible for dropping that voltage down?

Also, because it's an on and off pulsing it's hard to measure with the direct current Voltage range. Your reading is what you would expect with DCV.  If you set your multimeter to ACV you will probably get within the range predicted in Bert's guide.

It might be worth looking at the temperature sensor again cause even though the previous owner says he is confident he got the right one, maybe you shouldn't be confident since he sold it as a non runner.


__________________________________________________
11/1985 bmw k100rt (late model)  Vin. 0090567
 ~120,000 km
    

15Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Fri Sep 10, 2021 1:30 am

Laitch

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@daveyson wrote:Also, because it's an on and off pulsing it's hard to measure with the direct current Voltage range. Your reading is what you would expect with DCV.  If you set your multimeter to ACV you will probably get within the range predicted in Bert's guide.runner.
As daveyson indicates, wherever the test shows a measurement of Volts~, it means measure Volts AC.


__________________________________________________
1995 K75 81,000 miles
K100 First ride...then first push Usa-lo10
    

16Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Fri Sep 10, 2021 10:53 am

BespokeVillainy

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That's a hard one to get used to.
Hoping to have time to get on it this weekend.  The LEDs I ordered arrived too.👍

    

17Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Wed Sep 15, 2021 5:21 pm

BespokeVillainy

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So I just tested both HES sides and both sides would kill the LED light cold as well as heated with a hair dryer to the point I couldn't hold the metal plate.
I guess I will focus on the temperature sensor next since it seems to die every time as soon as the bike warms up.
Fingers crossed.

    

18Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Wed Sep 15, 2021 6:21 pm

92KK 84WW Olaf

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@BespokeVillainy wrote:So I just tested both HES sides and both sides would kill the LED light cold as well as heated with a hair dryer to the point I couldn't hold the metal plate.
I guess I will focus on the temperature sensor next since it seems to die every time as soon as the bike warms up.
Fingers crossed.
Temperature sensor does not cause a no running situation but it can cause excess fuelling by thinking its cold and over fuelling to compensate causing it to die.

If it thinks the bike is hot it inhibits a restart but does not cause it to stop.

If you change it make sure its for a 2v engine as the 4v looks the same but its not.


__________________________________________________
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 37,190 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
    

19Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Wed Sep 15, 2021 7:43 pm

BespokeVillainy

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I wondered if it impacted spark or fuel.  Thanks for that.  Would it be the same for air flow/air temp?
Whatever it is, it definitely is killing spark.  I watched it start missing and then die with the test light on the coil connections.
Thanks again.

    

20Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 12:41 am

Point-Seven-five

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Losing spark could be a failing coil. Early models had coil problems that led to a redesign around 86-87. A failing coil can sometimes work when cold and fail when hot for a while before completely going bad. If you replaced with an early coil, you may not have completely eliminated the coil as a source of the problem.

When you lose spark, is it on more than one cylinder? Are you losing spark on a pair of cylinders that share a coil? If you swap coils, does the problem move to the other cylinders?


__________________________________________________
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
    

21Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 6:30 am

92KK 84WW Olaf

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@Point-Seven-five wrote:Losing spark could be a failing coil.  Early models had coil problems that led to a redesign around 86-87.  A failing coil can sometimes work when cold and fail when hot for a while before completely going bad.    If you replaced with an early coil, you may not have completely eliminated the coil as a source of the problem.  

When you lose spark, is it on more than one cylinder?  Are you losing spark on a pair of cylinders that share a coil?  If you swap coils, does the problem move to the other cylinders?
If you haven't done the coil check you should do that first. I assumed it had been done.

Early ones are very very prone to this and failing after getting hot, been there. The coil cover doesn't fit if you mix old and later coils, either 2 old or much more preferably 2 later ones.


__________________________________________________
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 37,190 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
    

22Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 9:27 am

BespokeVillainy

BespokeVillainy
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I'm going to try rigging test lights to both coils at the same time and see if the missing and dying are the same.
Thanks!
If I can make the test rig stable I'll try and get video.👍

    

23Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 12:59 pm

92KK 84WW Olaf

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A coil issue affects one or both of 1/4, or alternatively one or both of 2/3. 1/4 fire together at the same time, 2/3 then do the same. 

The test is not fully reliable as it does not pick up if its failing under load due to weakness of spark.


__________________________________________________
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 37,190 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
    

24Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 1:07 pm

BespokeVillainy

BespokeVillainy
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I understand the batch fire of the system.  My dying happens both at idle as well as higher RPM when the bike warms up.

I just attempted to  test the secondary grounding of  Both coils at the same time using LEDs I picked up to test the HES but as expected I'm cooking them and have to quickly put my incandescent test light in as a substitute for one. I have also noticed that I seem to have lost my smooth idle.

    

25Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 1:42 pm

BespokeVillainy

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I'm definitely losing the grounding signal of the blue/black wire to the coil.  I can swap it and the black/red wire  and the problem follows the wire regardless of the coil.  It is also independent of either of the 2 ICM units I have.

    

26Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 1:50 pm

BespokeVillainy

BespokeVillainy
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Thinking about trying a jumper wire from the ICM plug back to the coil to see if maybe it's a bad electrical connection along the wire.

    

27Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 2:46 pm

92KK 84WW Olaf

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@BespokeVillainy wrote:I'm definitely losing the grounding signal of the blue/black wire to the coil.  I can swap it and the black/red wire  and the problem follows the wire regardless of the coil.  It is also independent of either of the 2 ICM units I have.
Anyone fill us in on the grounding?

Is it grounded through the ICU, possibly pointing to a fault in the ICU unit itself or in the plug connector?


__________________________________________________
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 37,190 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
    

28Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 2:50 pm

BespokeVillainy

BespokeVillainy
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 ran a jumper wire from the blue/black connector on the 1/4 coil to the back of the connector at the ICM and started it cold and let it warm up (with a test light hooked up to 12V+ and my jumper). The test light had a great signal until it started missing and the wire clearly lost it's ground signal.  Testing after it dies shows no ground signal on that wire.
What sensor gives the blue/black (#9 I believe) it's ground?  The black/red coil wire (#14 I believe) functions normally.


The fault is the same across 2 different ICU

    

29Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 3:27 pm

92KK 84WW Olaf

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Back to the known good parts bit. That fault has happened to other ICU units so possible to have 2 faulty ones. If I am right the ICU controls that earth. But if the earth is degrading does it mean the fault is in ICU or the other end as in a poor/damaged cable? The ground signal comes FROM the ICU? The ICU 'opens' and 'closes' the earth to control it? 

Does the rev counter behave normally during this?


__________________________________________________
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 37,190 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
    

30Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 3:35 pm

BespokeVillainy

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I saw that the other her blue/black wire goes to the rev counter (tach) and it does behave normally just showing the R.P.M.s dropping as the ignition misses.

    

31Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 4:27 pm

BespokeVillainy

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I cut the blue/black wire going to the rev counter just in case there was a short along it's path and got the same result.  Sudden drop in the ground signal on the blue/black coil wire when it warms.  I immediately tried swapping the ICU and it changed nothing.  Running out of ideas...

    

32Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 4:47 pm

Laitch

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@BespokeVillainy wrote:What sensor gives the blue/black (#9 I believe) it's ground?  The black/red coil wire (#14 I believe) functions normally.
Attached is an extract of the engine management schematic showing the ignition control unit and its coil wire terminal connections: the black/blue (sw bl) wire to terminal 14, and black/red (sw rt) to terminal 9.

When the engine stalls after warming up, are any of its spark plugs wet? 

K100 First ride...then first push Jetron11


__________________________________________________
1995 K75 81,000 miles
K100 First ride...then first push Usa-lo10
    

33Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 4:54 pm

BespokeVillainy

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Regardless of my hair dryer testing, If the two Hall sensors work independently to give a signal to each coil wouldn't it make sense that one might be failing at warmer temps?

    

34Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 4:56 pm

BespokeVillainy

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Yes, the plugs get wet from the injectors pumping with no spark

    

35Back to top Go down   K100 First ride...then first push Empty No spark Thu Sep 16, 2021 5:22 pm

daveyson

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It's the signal from the top sensor that allows the ICU to send an on and off ground through the black/blue wire.



Last edited by daveyson on Sat Sep 18, 2021 10:22 pm; edited 2 times in total


__________________________________________________
11/1985 bmw k100rt (late model)  Vin. 0090567
 ~120,000 km
    

36Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 6:08 pm

Laitch

Laitch
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@BespokeVillainy wrote:Yes, the plugs get wet from the injectors pumping with no spark
If you mean "all the plugs", you indicated that one coil was firing and the other would quit; the engine ran then stalled so half of it had spark until it stalled. Is that the case? The reason I'm asking is that you asserted previously that both hall sensors were operational. 

If both Hall sensors function, what could be happening is the air flow sensor/ air temperature sensor is sending faulty signals to the ignition control unit so the fuel injection unit can't interpret them optimally when it receives them, or the signals from the air flow meter are correct but the  fuel injection control unit is fails to interpret some of them correctly because of an internal defect.

If the signals from the air flow meter are incorrect the engine could start then stall from flooding because the mixture isn't being leaned as the engine warms.


__________________________________________________
1995 K75 81,000 miles
K100 First ride...then first push Usa-lo10
    

37Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 6:17 pm

BespokeVillainy

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Does the ICU get a signal from the air flow meter?

    

38Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 6:20 pm

BespokeVillainy

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Also, just thinking that the engine flooding from fuel wouldn't kill the signal from the a single secondary coil wire so sharply would it?

    

39Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 7:19 pm

92KK 84WW Olaf

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All things equal a failing air flow sensor affects all 4 cylinders equally. Filing Hall sensor only affects 2, 1/4 or 2/3.  Important to clarify if all plugs are same.


__________________________________________________
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 37,190 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
    

40Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 7:43 pm

BespokeVillainy

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Outside of something crazy going on inside 2 different ICU the HES was the only thing I could come up with that would stop the signal to 14 without stopping it to 9.  Assuming the hair dryer didn't get it hot enough, I ordered new HES set.
Will check back in after it arrives and I swap it.
Thanks.

    

41Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 7:52 pm

Arlina

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__________________________________________________
K100 First ride...then first push Eu-log10  K1100RS/LT - R1200RT - R1100RS (RIP) - Cagiva SST 350 Ala Verde - K75LT project - K75 Schurgers - K75S
    

42Back to top Go down   K100 First ride...then first push Empty Re: K100 First ride...then first push Thu Sep 16, 2021 9:02 pm

BespokeVillainy

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It is a wealth of knowledge and I reference it often.👍

    

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