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151Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 4:16 am

Rabidchiwawa007


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I figured as much. I remember going through all that myself when I first bought it thinking 200 seemed a bit high. Alas, here it is: http://www.beemerboneyard.com/11001461839.html It's all lies... LIES!! I wonder if the mileage was faked too.

    

152Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 4:29 am

RicK G

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I was forgeting it's a 16v so you can add another 8psi as they are 11 - 1.
I have never come across a wrecker that will say mate its f^*#d but I am charging top dollar because I am a greedy asshole.
I bought an auto trans for a car some time ago and was told it's real good we drove it in here and round the block before we pulled it out and it shifts as smooth a velvet. So I took him to task and got half my money back.
I only wanted it so as to have one to reco then swap them over but the 1st gear clutch pack was so bad that it could not have engaged if you put 10000psi into the servo let alone 150psi.
I did a total reco and then used it and it did shift like velvet.


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

153Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 4:37 am

Rabidchiwawa007

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Hah, nice. Gotta love it when that happens. My dad's '69 BSA Rocket 3 was sold to him for dirt cheap because the guys that were trying to get it running didn't realize that all those old British bikes did everything backwards. They couldn't get it started because of some simple backwards thing (I completely forget what), so my dad bought it, spent 5 minutes on it, fired it up and now has another beautiful bike.

That K engine is a little better than it looks though, as I managed to talk him down a couple hundred from what it was posted at.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

154Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 8:50 am

GerryP

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Hi Rabidchiwawa007,

Just back from a nice long weekend in Somerset on my K. Glad to see you're making some progress.

I've watched the videos and I agree the spray pattern from the injectors is very blobby. I think they may be beyond chemicals in the tank, you may need to send them to a professional cleaner, but Tecron is worth a try first.

The fuel filter is definitely in with the arrow pointing in the direction of the fuel flow?

...just occurred to me. There is an earth connection under the battery tray. It earths the ignition amplifier. Its easily forgotten and its in a place where it collects all sorts of dirt and corrosion.



Last edited by GerryP on Tue Jul 02, 2013 9:19 am; edited 1 time in total (Reason for editing : addition)


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155Back to top Go down    reminder on Tue Jul 02, 2013 11:03 am

ibjman

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reminder, compression test must be done at Wide Open Throttle........and a minimum of 6 pips test per cyl. I would be looking for 140 but seems nearly correct.

Also, If I have good cylinder balance at the vacuum gauges, I would definitely not change anything at the throttle butterflies.

The throttle body air bypass screws should have their final setting at about 1500 rpm

    

156Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 1:11 pm

Rabidchiwawa007

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@gerry: I took the ignition amplifier out and reapplied heatsink paste and cleaned all that up as well. Made no difference. The fuel filter is definitely in the correct way. The hose that comes from the fuel pump connects to the side of it that says "IN".

@ibj: if it sounds like the throttle butterflies are opening at different times and causing the stuttering, shouldn't I re-sync them? It seems easy enough. I'll count the turns in on the air bypass screws and if they're all similar, I'll rethink, but it sounds like the butterflies need help?


If I were to go buy brand new injectors, I'd rather buy them not from BMW for pricing purposes. I see quite a few replacement injectors out there from Ford cars / trucks and the such for the 8valve K-bikes. Would these also work for the 16valve bikes? What should I be looking for?


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

157Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 1:34 pm

keefk1100lt

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Just read through this thread...

As I understand it, the engine is a replacement, but the throttle bodies are the originals, with circa 100k miles on them.

Question. When you start the bike from cold, do you use the choke? If so, you're opening the butterflies a tad, as the "choke" on these engines isn't as much a choke as a fast run device.

So, could your warm running problem be down to worn butterflies? Either the butterfly flaps themselves or the actual throttle bodies?

    

158Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 1:42 pm

Rabidchiwawa007

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Yes, I do use the choke, but it will start just fine without it. I've had the TBs off a few times and everything looks fairly okay. I'm not sure what I'd be looking for, but nothing looks terribly worn around the edges of the butterflies or anything.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

159Back to top Go down    sync on Tue Jul 02, 2013 2:12 pm

ibjman

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The brass screws are "adjustable air bypass tunnels" around the outside of the butterflies. Their only function is to balance out differences between the flow rate of one butterfly compared to the others. If you can achieve a great balance on for gauges simultaneously, by turning the brass screws, the butterfly throttle linkage set screws should never be changed. If they have already been messed with ie from you or a previous owner....then you have a more difficult process in re-achieving the proper balance.

Scenario #1: You can indeed get a good 4 gauge balance with the bypass screws (as designed):

The bypass screws should be only 1 turn to 1 1/2 turns open when balance is achieved)
In that case, re-check the balance at slow idle., then advance the center idle stop screw to bring the speed up to 1500. and re-check balance. The final balance is set at 1500. Last, back off the stop screw till you have about 900.

Scenario #2 You would not be able to obtain a balance by regulating bypass air via the screws.
In that case you have a long day ahead of you, since moving 1 mechanical adjustment screw on the linkage affects all the others. The idea would be to get all the butterflies fully closed but only barley. Hence when one butterfly "just cracks" all the other three do the same.
I do this with the butterflies off the machine, by holding all the throttle bodies up to a bright light and sight through for the slightest amount of light shining through the barely open butterfly.
Another method is to use a very small drill bit (as a feeler gauge) and adjust each butterfly till the smallest bit will barley stay in place or barely fall out when pinched between the butterfly plate and the throttle body wall. This way you are trying to obtain identical opening of all 4 plates.

In the final adjusting, we have to be sure that we have removed all 4 screws and thoroughly washed out all the air passages with carbi cleaner and the screws also. Be sure the O-rings on the screws are still good.
LIGHTLY seat all four air screws at the bottom of the bore & back them out about a turn and a quarter.

Start the bike and adjust the idle stop screw to maintain a slow idle. Balance the 4 throttle bodies with the air bypass screws, re-adjusting the idle stop screw as needed to maintain an idle speed. Try to avoid having the bypass screws so far open that you can not get a slow idle with the linkage stop screw. You want to have idle speed adjustability both ways with the mechanical stop screw when you're done.

I'm wondering if you are indeed using 4 gauges in your balance procedure & not trying to do it by moving only 2 gauges back & forth between cylinders.

Also, when balancing, it's best to have a tee connector in the #4 vacuum sense hose so that the FPR can remain connected during the procedure.

Please review and tell us how close "Your" balance is to what I've described.

Regards, ibj....

    

160Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 2:47 pm

Rabidchiwawa007

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I, in-fact, only have one vacuum gauge, so my balance method was nothing like your correct way. I used it to set the air bypass screws a little while ago and it went fairly well. The idle improved quite a bit and got much smoother. I would need a set of 4 gauges to do the butterflies.

It looks like the blue paint on the butterfly adjustment screws is still intact, so maybe I shouldn't mess with them. I just called the last mechanic who worked on it to see if he synced them, but he had not touched the butterflies. This means the butterfly sync is likely still factory set, 100k miles ago.

I'm going to go pick a heat gun and test the hall sensor. I'll also look in to some new injectors.

Would the "Standard FJ27" injector work with the 16valve bikes?


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

161Back to top Go down    Re: Engine misfiring when warm on Tue Jul 02, 2013 5:11 pm

Rabidchiwawa007

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I ordered a new (used, working) hall sensor from beemerboneyard. The hall sensor on it has a slightly messed up connector on it. The plastic is all missing, but all the plugs are there, so I had it plugged in to the harness with electrical tape all around it.

I'm not completely sure if the hall sensor was the problem, but I heated it up a little and got a small amount of stuttering while the bike was cold. Then, of course, I figured I'd heat it up more to see if it would give me a clearer amount of stuttering. I farking melted the plastic parts on the hall sensor, which threw the elements out of their place. Slightly embarrassing :\, but a new one with a better connector should be here this week and then we will see how it runs.

I also took a resistance reading on the air temp sensor in the air box. It read about 1.98k ohms. It's about 78F here today, and probably not much warmer in the air box.

I also sweep tested the TPS, it passed just fine.

So now I wait for a new hall sensor.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

162Back to top Go down    Re: Engine misfiring when warm on Sat Jul 06, 2013 5:34 am

Rabidchiwawa007

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New hall sensor came. Installed, issue remains. It seems at this point that whatever component is actually failing is almost completely failed. The bike now almost just runs on 3 cylinders (2 maybe?) I haven't cleaned the injectors yet, but have some Bosch type II (the 4-hole spray ones) on the way, to be here in a few days.

If the new (reconditioned) injectors don't do it, I'll be very suspect of the coils and ICU.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

163Back to top Go down    Re: Engine misfiring when warm on Sat Jul 06, 2013 5:28 pm

K-BIKE


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I recall years ago a colleague had a VW Beetle which had the same issue, misfiring when warm, he finally isolated it down to the coil and we conducted an experiment with an oil bath on a heater. Cold it was fine but as the temperature came up the resistance to earth went down until it was quite badly shorted out. it would be interesting and possibly revealing if you clipped a strobe light onto the suspect lead to see if it was putting enough out to trigger the strobe when misfiring. Or when hot measure the coil resistance to see if it has changed from when it was cold.
Regards,
K-BIKE

    

164Back to top Go down    very intresting on Sat Jul 06, 2013 6:10 pm

ibjman

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I like that.......put a timing light on the suspect coil plug lead to see if you can see any irregularity in the flash......I think I still have one of those inductive timing lights in my kit somewhere????

    

165Back to top Go down    Re: Engine misfiring when warm on Sat Jul 06, 2013 8:08 pm

Rabidchiwawa007

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I should be able to get something like that pretty easily from harbor freight. Also, with how consistent it is now when it's warm, I could simply unplug the plug caps one by one and see if the choked idle goes down. I say choked because its a lot more obvious above the 1k idle.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

166Back to top Go down    Re: Engine misfiring when warm on Sat Jul 06, 2013 9:19 pm

charlie99

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if your getting a timing light
get one with the advance timing built in to check the timing in the future ....I don't think they are that much more over there ...

just a thought .


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

167Back to top Go down    Re: Engine misfiring when warm on Sat Jul 06, 2013 11:54 pm

Rabidchiwawa007

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Rick posted this link awhile ago in regards to replacement coils: http://www.euromotoelectrics.com/SearchResults.asp?Search=coils

Which of those dynatek coils would be the one to get for my '92 k100?


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

168Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 12:43 am

RicK G

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Not the dynatec coils but futher down the page, this


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

169Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 12:53 am

Rabidchiwawa007

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Ah, I see. I saw those, but from your previous post thought that you were referring to the dynatek as a low cost alternative. I'm thinking of just replacing both coils because of their age and miles. Is there a cheaper alternative to the stock coils? If not, I'll just buy the one.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

170Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 2:46 am

RicK G

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Try some of the dealers they may sell a bit better but EME is the best I have found.


__________________________________________________
"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

171Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 5:02 am

Rabidchiwawa007

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Thanks Rick, I'll check around.

So, my new injectors came today. They are the Bosch Type II injectors with the 4-hole spray. Installed them, and wow! much better. The bike still misses a bit when it warms up, but at least it's running on all 4 cylinders again. Those old dirty injectors certainly weren't helping at all.

I didn't get a chance to pick up a strobe timing light yet, but I did take measurements on the coils again after getting the bike to operating temperature.

Here are the measurements I posted previously with the coils cold:
Coil for 2/3: 13.05k ohms at orange towers /// 0.9 ohms at primary coil
Coil for 1/4: 12.92k ohms at orange towers /// 0.9 ohms at primary coil

Now, here are the measurements with operating temp coils:
Coil for 2/3: 13.91k ohms at orange towers /// 0.9 ohms at primary coil
Coil for 1/4: 13.91k ohms at orange towers /// 0.9 ohms at primary coil

I also figured I would take the measurement of the wiring harness to the coils while I was in there, but not sure if it tells me anything:
Wiring harness to coil for 2/3 read "-10.94k ohms"
Wiring harness to coil for 1/4 read "-5.75k ohms"

I honestly didn't know negative resistance was a thing, but that's what it said. When I would swap the multimeter wires within the same coil wires, it wouldn't read anything, but reads the 'negative resistance' the other way. I feel that the resistances of those wires, from the harness to the coils, should be the same regardless of what they read?


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

172Back to top Go down    Diode? on Sun Jul 07, 2013 5:34 am

ibjman

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Sounds as if when measuring the resistance of the wiring harness' you must be testing through a diode mounted somewhere in the harness? hence you have to have the meter the incorrect polarity to get any reading at all.

I'm sure RickG or Charlie99 will be able to advise you on the specifics, since I just have no knowledge of this.

I would guess that maybe there could be a diode soldered in to each of those wires between the 2 points????
If so, a deteriorated diode or connection from either end of it to the wire could certainly seem to be a problem.

This is like a soap opera!!!! I can't wait to read the next episode. Hopefully the season will not end before the solution is revealed!

Regards, Ibj...

    

173Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 5:45 am

Rabidchiwawa007

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Interesting. I'll take a look at the wiring diagram (don't know why I haven't yet) to see where those wires go. Hopefully RickG or Charlie99 can chime in on that too. Either way, the injectors are a huge step forward. It's back to smooth running beyond 4k rpm.

Hah, I know, so many posts. When I'm all done here, I'll go through the thread and collect all of te issues and how-tos and write them up for that section of the forum.

I was curious as to the warm resistance reading on the coils as well. It seems as if it's within normality to me, especially since both are the same, but all this stuff is fairly new to me.

Will type back when I figure out those wires.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

174Back to top Go down    Try on Sun Jul 07, 2013 5:49 am

ibjman

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Try disconnecting the wire harness from the instrument cluster and re-testing.......could be that you are getting a lower than normal resistance (or visa versa) on one of the sides because of the wire to the tachometer that is piggy backed on to only 1 of the 2 coil circuits

    

175Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 7:00 am

charlie99

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you may have found an issue
the output switching devices that turn the coils on are igbp devices and have some resistance ...or conduction to earth and some path to the b+ (12 volt positive signal ) though the internal connections from leakage or failure of protection circuitry ..depending on the polarity of the measuring device ..(multi meter ) ...the negative reading you are seeing is leakage of voltage into the multimeter circuit from the electronic in the ecu . capacitors diodes etc .

it would be likely that one of the devices could be damaged and reacting to a heating effect ..at a guess, a protection diode .. internal to the ecu

I had a similar issue on some coil packs on a locally produced car ...(6 cylinder holden . chev )

what had happened was that the earth was not properly connected after some work ....all was ok till I turned on the head lights a few days later ....the car just stopped dead ...after finding the problem all seemed ok ....till I took off on a longer than normal trip ..(over an hour of travel ) about an hour and a bit the car coughed and spluttered etc and actually died ...like it was out of fuel or bad fuel ....after letting it cool down all was good ...for a few miles up the road then would die again ...I dumped the fuel ...cleaned up the filters on the fuel injection etc ...but couldn't get it to run for more than a few minutes ...during the day ....at night ...no problems ...go figure .
changed out the coil firing igbp switches ( in this case full module ) ..with a slightly later (and supposedly better unit ....never an issue since .

folks in the know new of these failures ...but could never figure out why ...they just sold lots of parts over the years ...or upgraded to the later unit .

the problem was that the igbp coil igniters had become lossy and sensitive to heat from the high voltage generated by the alternator going over voltage during the lights on and off whilst running ..(without a proper earth ) ....this had damaged the switches and they were running flat out not able to dissipate the heat during the day ...at night the difference was greater and they ran longer ...just or whilst going to work in the cool of the new day

it might be an idea to borrow another ecu for testing purposes ....

good luck



Last edited by charlie99 on Sun Jul 07, 2013 7:08 am; edited 1 time in total


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

176Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 7:06 am

RicK G

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Disconnect the battery and give the components time to discharge (10 min) then measure resistance again you may find that there was some stray voltage hanging around.
The increase in resistance in the secondaries when hot is normal.
can you give me a link for the 4 hole injectors I have been hunting but havent bagged any as yet.


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"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

177Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 7:11 am

charlie99

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me too rick (the injectors )
blakey has some but out of a ford ...and I recon the flow rate will be too high ..but ill wait and see


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

178Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 7:17 am

RicK G

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One thing I found about injectors is that the standard for measurement is 3 bar and the Ks run at 2.5 so you need to do some maths unless it is stated as a direct replacement. The only ford injectors that are interchangable are for the 5lt V8 from any of the range up till late 90s with the sequential injection. The old windsors.


__________________________________________________
"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

179Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 2:00 pm

Rabidchiwawa007

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Here's a link: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&vxp=mtr&item=190865605539
Nice deal, and he reposts it after you buy it because he's got a lot. They should be a direct replacement. They are 17lbs @ 3 bar. 2.5 bar is 83% of 3 bar. If the ratio is direct, that comes out to 14.16 lbs @ 2.5 bar According to the auction listing, they'll fit the following:

Direct Drop-in Plug & Play Fitment:
83-89 K100RS/RT
86-91 K100LT
83-89 K100
88-93 K1
84-85 (9/85) 318i

The '90-'92 k100rs is just a k1 with the k100 fairing.

Shipping might cost a bit, but it was a fairly small box they came in.



Thanks for all the info regarding the coil harness wires. An ecu is a tough thing to find, unless a dealer or the local bmw authorized shop is willing to let me borrow one (unlikely). The ecu for the '92 k100 is different from the older Ks, correct?

I'll take a look at those options when I get a chance and also see if I can find an ecu near here somehow.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

180Back to top Go down    Re: Engine misfiring when warm on Sun Jul 07, 2013 3:05 pm

charlie99

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I would do the measurement again ,,,with the instruments unplugged ...to confirm
doesn't the 1100 and 16 valve k100 units have an ignition amplifier separate to the ecu ?



Last edited by charlie99 on Sun Jul 07, 2013 4:04 pm; edited 2 times in total


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

181Back to top Go down    yes on Sun Jul 07, 2013 4:00 pm

ibjman

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The ecu's are different between jet-tronic & motronic
Dealer cost new would be prohibitive at nearly $1400. Dealer is unlikely to loan you one for fear of damaging it.
It you can find a fellow rider that has a like vehicle, do not install his in your bike to see if it works, Install yours into his bike to see if it runs equally bad there.
This could save you from destroying his ecu if you happened to have an unfound fault somewhere in your wiring.

    

182Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 1:06 am

Rabidchiwawa007

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eek, pricey. I hope it's not that. I took a look at the wiring diagram and see that one of the wires to the coil does indeed include a wire to the tach, and that wire has a lower resistance.

I'm not sure what sort of resistance I'm actually looking for on these wires, and don't know what to set the ohm meter to for the B/L wire to one coil or the B/R wire to the other. As silly of a question as it may be, how would I test those harness wires for correctness? One multimeter end to B/L and the other to ground? Then same for B/R? And then what should the multimeter be set to, 200, 2k, 20k, 200k, or 2000k? I tried it a couple different ways and thought it was interesting that I got completely different readings with the multimeter set to different spots. For example, on 2k, it read 530 ohms from B/R to ground, but on 200k, the reading was 126.9k (if I'm reading that right). I know this really has more to do with how to use an ohm meter >< but I can't really find anything online.


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1968 BSA Lightning
1991 BMW K100RS 16v with K1100LT fairing
    

183Back to top Go down    in the diagram on Mon Jul 08, 2013 2:56 am

ibjman

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I'm not sure if my diagram is the same as your machine, but I think so.

Note: Remember, when using the multi meter that although the black lead is always left connected into the COM port of the meter, You have to move the red test lead over from the Volts Port to the Ohms post, when switching the scales on the meter from DC volts, around to Ohms. Common sense, I know, but all to easy to forget when changing test functions.

As I see it, if"
#1 you disconnect all the primary wires from the coils and
#2 you disconnect the wire harness connector from the Ignition control module.

You would find pin #14 in the harness connector for the ICU, should be a Black/Blue wire.
you would find the Black/Blue wire removed from the ign. coil.
Connect one lead from the ohm meter to the harness end pin receptacle and the other lead of the ohm meter to the wire that was removed from the coil spade. Put the Ohm meter on the lowest scale. The resistance from one end of that Black/Blue wire to the other should be zero or very close to it.

Use the same procedure on pin #9 at the ICU harness connector testing through the Black/Red wire to the end removed at the other coil. Again, expect zero or very close resistance across the Black/red wire.

Next, at the coils there should be a green/yellow that connects at each coil. Connecting the ohm meter across the 2 coil spades on the green/yellow the resistance again is zero.
Additionally leaving one ohmmeter lead on one of those green/yellow spades, move the other ohmmeter wire to pin #10 at the ICU connector (also Green/Yellow). Same result, no resistance.
Following that, if pin#10 checked out correct, remove the second test lead from the coil end of Green/yellow and move it to the back of the handlebar kill switch, green yellow wire there. All should show very low or no resistance. Now, with one lead still on the green/yellow wire at the kill switch, connect the other test lead to the green wire at the kill switch. With the switch "on" the resistance should be near zero, switch the kill switch off, resistance will jump up to infinity or HI, switch it back on, resistance should fall back to zero.

Last, check the Tan ground wire spade at each coil with one end of the ohmmeter with the opposite lead of the ohmmeter lead at the negative battery post, the frame metal, the ground strap at the side of the trans case....etc.......all zero or very low.

If all that checks out, reconnect the Green/Yellows at the coils. Reconnect the Black/Red at it's coil & reconnect the black blue at the other coil. (I believe these only go one way and cannot be reversed with the Green/Yellow ones. For now, leave the Tan ground leads off the coils.

Now, you have the primary circuits on your coils fully connected to the ICU harness

Go to the ICU harness and test with the ohmmeter between pin #14 & #10. This should be very close to equal what you read at the coils (3 Ohms?)

Next test between Pin #9 & Pin #10, again looking for nearly the same value as your original primary side coil spec. (3 Ohms?).

Once all those continuity tests are complete, reconnect everything (including the tans at the middle spade on the coils).

Change your red mult-imeter lead from the ohms port, back to the Volts port. Switch the meter scale to 20V DC.

Turn the IGN switch to "RUN", Turn the kill switch on.

Test the voltage across the battery + to - , record the value with the switches on.

Remove the test points & connect the red lead to Green/Yellow at either coil. Connect the black test lead to the negative battery terminal. The voltage should be the same as battery voltage or slightly less. Leave the leads connected, cycle the IGN/Kill switches several times look for the same readings at each "ON" cycle.

    

184Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 5:24 pm

Rabidchiwawa007

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Does ICU refer to the motronic computer, or the other computer? The Clymer manual shows all the coil related wires going to an "Ignition Output Stage", and then a Black wire and a Black/White wire going to the motronic computer. On the motronic computer connection, the pin 14 slot is empty. Based on the pinout below, from Frank Warner, should I be using pins 1 and 2 on the motronic connector?

(Sorry for the sideways picture)








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185Back to top Go down    My ref. to ICU on Mon Jul 08, 2013 5:48 pm

ibjman

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My references to ICU mean the small black Ignition box (Ignition control unit) above the radiator just behind the steering bearings and under the frame backbone.

My references to CPU, ECU, FCU, etc would be referring to the engine management computer under the toolbox.

I was referring to testing the wire for the primary circuit to/from the ignition coils.

    

186Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 5:57 pm

Inge K.

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The Motronic unit controls both the ignition and injection...no black box under the front of the tank on the 4V's.


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187Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 6:01 pm

Rabidchiwawa007

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Inge beat me to it. Here's what under my seat looks like:

(unplugged connectors so computers were more visible)
Motronic is the one with the orange sticker. The other one... I'm actually not sure what it does.


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188Back to top Go down    OK on Mon Jul 08, 2013 6:03 pm

ibjman

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I was going off the 2V k100 print out, entirely different than this. Dang! I had a lot of time in that post too!
Sorry for the mis-understanding.

    

189Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 6:05 pm

Rabidchiwawa007

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Well, I would thank that post would still be valid, I just need to find the right pins on the motronic connector. Do you have a pinout of the ICU that you (ibj) were referring to so that I can possibly cross-reference pins based on how those ones are labeled?


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190Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 6:09 pm

Inge K.

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@Rabidchiwawa007 wrote:The other one... I'm actually not sure what it does.

ABS.


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191Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 6:10 pm

Rabidchiwawa007

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Really, all that just for ABS? Good to know though, thanks Inge.


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192Back to top Go down    It looks on Mon Jul 08, 2013 6:12 pm

ibjman

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No I don't have the printout.

Looks to me that from the hand drawn diagram, that pin #1 goes to one of the coils and Pin #2 goes to the opposite coil. Seems easy. And the other 2 (not Tan) wires on the coil go somewhere else, not shown in the diagram.
I'll GUESS that the wires from the coil in the diagram labeled G, go to maybe the kill switch?????

At any rate, if correct....you would hook 1 lead of the Ohmmeter to the green wire at it's source and the other lead to pin #1 in the harness connector, note reading, then move that lead over to pin #2. Both readings should be nearly the same low resistance like about 2-3??? Ohms as you originally measured at the coils themselves.



Last edited by ibjman on Mon Jul 08, 2013 6:20 pm; edited 1 time in total (Reason for editing : better information, possibly)

    

193Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 6:15 pm

Rabidchiwawa007

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I just took another look at the coil wiring. It looks like the tan wires you refer to for the older models don't exist on these. I wonder where it grounds to...

Edit: Ibj, your previous post is still somewhat valid, however the wires from the coils' harness go through the ignition amplifier first. I believe that's why I was still getting odd readings that I shouldn't get from testing straight through a wire. I'm going to test at the ignition amplifier and the disconnected coil wires and see what I get.


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194Back to top Go down    All tests on Mon Jul 08, 2013 6:28 pm

ibjman

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If the test from the MCU unit connectors # 1 & 2, through the wire and then through the coil to the connection for the "G", differs from the test across the coil alone then test just the "Harness" wire from the coil to the MCU plug with both ends disconnected.

The colored wires on the coil aren't essentially "Ground" don't get confused on that. I believe that the "G" wire may be positive power (constant) from the kill switch to both coils. The wires from the coils back to the MCU get switched on & off (to ground) through the MCU, in sequence as is indicated by the input signal from the hall sensors TO the MCU.

When the Hall sensor see's it is time to fire a plug, the MCU interrupts the ground to the either coil as needed.
When the ground interrupts, the magnetic field in the coil collapses creating the high voltage spark out the tower(s)

    

195Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 8:07 pm

Rabidchiwawa007

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Correct, I've light-bulbed over the past hour. I get how it all works now for the most part. Well, here comes a ton of measurements:

For reference, my multimeter gives a reading of 0.9-ish ohms when I touch the two leads together.

These are essentially one end of the wire to the other:

Coil ground to frame: 1.1 ohms

Black/Blue coil harness wire to ignition amp connector pin 1: 0.9 ohms
Black/Red coil harness wire to ignition amp connector pin 6: 0.9 ohms

Black wire, Ignition amp connector pin 2 to motronic connector pin 1: 0.9 ohms
Black/White wire, Ignition amp connector pin 7 to motronic connector pin 2: 0.9 ohms

Ignition amp connector ground wire to frame: 1.1 ohms

-All of these measurements so far seem to have no, or almost no, resistance, which is a pass.

Ignition Amplifier: The way this works, as I can see, is that the coil wires, Black/Blue + Black/Red, go from the coils to ignition amp pin 1 (black/blue) and pin 6 (black/red). From there, the ignition amp routes a black wire (was black/blue) from pin 2 and a black/white wire (was black/red) from pin 7 up to the motronic connectors pin 1 (black) and 2 (black/white). As such, I measured the resistance on the ignition amplifier between pins 1/2, and pins 6/7.

Ignition amplifier pins 1/2: 145.9 ohms @ 200k multimeter setting (would this be 145.9k ohms?)
Ignition amplifier pins 6/7: 146.2 ohms @ 200k multimeter setting
-Both of these measurements are quite similar, so I would assume the ignition amplifier is in good shape.

Now that I got all of those individual measurements done, I tested from the disconnected coil wires, through the ignition amp, and up to the motronic connector pins 1 and 2. The interesting part was that both coil wires gave a reading with either motronic pin.

Coil wire Black/Blue to Motronic connector pin 1 OR 2: 30.2 ohms @ 200k multimeter setting. (is this lower due to the tachometer wiring?)
Coil wire Black/Red to Motronic connector pin 1 OR 2: 146.5 ohms @ 200k multimeter setting (expected, as the ignition amplifier puts out 146.2(k?) ohms here.

I then tested with one lead on motronic pin 1 and the other on motronic pin 2 (because of how the previous measurements acted.

Between Motronic pins 1 and 2: 1.8 ohms @ 200k multimeter setting

Now for the green wires from the coils to the switch, with switch turned off.

Green coil wire to Green kill switch wire: 1.1 ohms, for both green coil wires

Another interesting thing:

Green coil wire to Green/Yellow wire in kill switch: 51.7 ohms

Green coil wire to Black/Yellow wire in kill switch: 27 ohms

Finally, voltage test:

Battery Voltage: 12.43v
Coil cyl 1/4 green wire to negative terminal: 12.38v
Coil cyl 2/3 green wire to negative terminal: 12.37v

It seems that most of these measurements passed the test. There are just a few interesting ones in there that I don't understand.

(nearing 200 posts!)


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196Back to top Go down    I don't think on Mon Jul 08, 2013 8:38 pm

ibjman

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I don't think you should be ohming THRU the IGN amp (whatever that is ( thought it was all inside the main computer box.

basically, you are trying to test from the management computer plug through the wiring only to one connector at the coil....through that coil into the green wire......through that wire and back to it's end.

I don't see how you can get a measurement with any wires hooked up to the Ignition amp....but I really have no idea what the system looks like.

    

197Back to top Go down    Re: Engine misfiring when warm on Mon Jul 08, 2013 11:14 pm

Rabidchiwawa007

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I think what most of that was, was testing for good wires and good connections. I don't know how the ignition amp works exactly, I just know it adds resistance to the system before the wires get to the coils..

Here's a complete diagram of the 'engine wiring harness' for reference:

I don't know what that little box next to the oil pressure switch and clutch switch is.. it's not labeled, but seems to have something to do with that green wire from the coils.


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198Back to top Go down    IDK on Mon Jul 08, 2013 11:43 pm

ibjman

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IDK what that is either......strange, it only has dotted lines going to it??? Perhaps some optional accessory?

The diagram appears to show the second wire from the right on the multi handlebar switch is Green & goes direct to the coil.

    

199Back to top Go down    Re-reading your old posts. found this quote on Tue Jul 09, 2013 12:12 am

ibjman

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QUOTE:

I do have one of those Harmann chips in the computer, and I think those are designed to send less fuel thereby smoothing out the power

Is it possible to remove the custom chip and re-install the factory chip? I would think that a lot of the oem specs for adjusting C/O and tps would not be applicable with a modified engine program.

    

200Back to top Go down    Re: Engine misfiring when warm on Tue Jul 09, 2013 12:21 am

Rabidchiwawa007

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The Harmann chip is supposed to just be plug-n-play with the factory set system. I don't think it's the cause of the issue because nothing changed when I put it in. It gave it a smoother power-band and slightly less power (just as it said it would), but didn't cause any issues. I could certainly try it though.


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201Back to top Go down    Slightly less power? on Tue Jul 09, 2013 1:18 am

ibjman

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Slightly less power as in "leaner", or reduced IGN timing?

Possible. My point was.....it may have achieved those goal by changing the factory fuel mapping.

If so, The adjustments to the CO and TPS may need to be outside the normal spec to compensate.
All Hypothetical.
As we go I'll learn more about going back to a point in time when this first began.

    

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