Hello!

So the bike is K1100RS 1996 and it has roughly 130 000km on it. This is my first bike and i have basically no experience with motors, in any vehicle. But i think i am doing OK, this forum and others have been a gold mine for knowledge. I will take it to the shop only as last resort.. trying to learn how to take care of it myself. It was running last summer and a lot has been renewed during winter days. After all the parts I found out to be defective and replaced, I would have assumed that it runs better, not other way around.. 

Against all odds it started after the rebuild. It is running rough on idle, not very good, have a look at the video.  In both videos it is running quite cold, less than 5 minutes.

It has..
-new throttle body rubber boots (old ones had cracks)
-used but good throttle body to airbox rubbers (old had cracks)
-throttlebody butterflies synched with the water method.. so that same amount of water flows through
-new air filter
-new fuel filter
-outside of the tank all fuel lines new
-new injectors EV14
-new NGK 5ohm leads and DR7EA sparkplugs
-valves clearances adjusted.. 10 new cam followers.. (sadly after adjusting one is still out of range. it would have needed 2.45mm cup, but only 2,50mm was available)
-new crankcase breather hose
-new hose that connect on back to all four throttlebodies


So basically everything that is connected to air intake is renewed, so not likely to have leaks there (didn´'t check with gas...yet..)

And gasoline distribution should be in order, at least it was running last summer and now there are renewed lines and new injectors.

When i removed the exhaust, 1&4 were black on the inside, as one would assume.. but the 2&3 were white. Then proceeded to see if the plugs were different colour, but they were all so black and covered in oil that i could not tell. But leads were in awful shape, very corroded, previous owner had put NGK plugs without those hats, so it had arched quite much.

After it didn't run so well, i took the spark plugs out to see if the gaps are okay, they were all between 0,6-0,7mm. But the colour was different, once again 1&4 were more black, and 2&3 white. Considering that it had been running max 20 min, quite noticable differences. Then put it back together and sprayed water to exhaust pipes, to see if pipes are hot evenly. But 1&2 are noticeable colder than 2&3.

Is the most likely defective part causing bad ignition in 1 and 4 cylinders 1&4 ignition coil? Connectors that connect to ignition coils both give 12V on one of the connectors. Am I on right track here?  Or can there be problem with mototronic?

Second problem is that ticking sound.. i have read that i could be caused by bad timing chain tensioner, but the sound seems to be coming more from the back side of the motor. Another is that the injectors are ticking.. but not sure about that.. what are the expert opinions on the ticking sound? The slightly tight valve is cylinder 4 exhaust, it should be 0.25-0,30 but 0,25 does not go between.. only 0,20.. if it is so tight that tills.de does not even sell cam follower that thin, what is the next thing that must be changed to fix that gap?

Trying to gather all the needed parts in one order.. but as i have experienced, that rarely is the case  

Best Regards
Saints

Wild guess since a pair of spark plugs were black... remove cover over plugs and turn off the lights, the sound almost sounds like arcing with the high voltage jumping to ground. It's a quick check and eliminates on possibility. There is also a correct way to route the plug wires.

Greetings.. to the correct way of the cables, didnt put them very nicely back as i thought i will be takin coils apart very soon..

Took shot in the dark, pitch black when engine running, so no arching?

With a pair of spark plugs black it sounds like a coil as the fire together. Maybe check the leads  on the primary side. Check the resistance of the coils  on the one labeled 1-4. Specs are available online. It is simple stuff but troubleshooting is a methodical process.

As Bricklayer mentions, it sort of looks like one of the coils is giving you trouble.  Another test you could do would be to swap the coils.  If the problem switches to #2 and #3 you can be pretty sure the coil has a problem.  If the problem doesn't move, the cause may be the Hall Effect Sensor or something in the ignition controls.

Coil resistance specs with ignition off and coils disconnected, from BMW's Motronic 2.1/2.2 Diagnosis Manual:

Tried to do resistance measurements but i think my multimeter is busted.. only reading i get is 0L, tested it to few resistors and same outcome. But that is that.

I swapped the coils and the problem persists the same, at least temperature stays the same.. no.1 is the coldest, 2&3 are hot and 4 is hot, but not as hot as 2&3. So would this give pardon to the coils? Hard to picture that problem could be in the leads, they are new and seem to connect very well, nothing is loose and all contact surfaces are clean and great condition. But everything is possible.

Is there a way to test the hall effect sensor?

Sounds like the coils are okay.  Try pulling the #1 spark plug and see if it sparks with a good spark then do the same for #4.  That will confirm that the cylinders are getting spark and the problem is fuel supply.

#1 and #3. Or #2 and #4. #1 and #4 are on the same coil. Or did I miss something obvious?

So 1 and 4 are colder, so I'd also test the leads or swap them. The high tension circuit's don't return to the battery, for example 1 goes to 4 and then back again, so they depend on each other. If no luck I'd swap 1 and 4 spark plugs with 2 and 3.

Got a new multimeter and measured the coils, both have 0,5 ohms and 12,5 ohms. Also tested with the leads swapped, made no difference. 

Interesting was that when we tested for spark (injector plugs disconnected). We removed 1 spark plug at a time, grounded and cranked, we seemed to get even spark on all plugs. 

Tested also for compression, 1 plug out at a time. All gave ~11 bar compression at normal throttle position and ~15 bar throttle fully opened. seems quite high (?). Motor temperature was not optimal for compression test, around 50°C


Tested for intake leaks with butane/propyl gas, found no increase in rpm

Then I loaned a timing light and thought that maybe I can check that.. connected the injectors again and put the motor running ~1000rpm and plugged it to:
no. 1 lead: Just occasional flashes.. 
no. 2 lead: flashing quite good.. kind of... half of the time
no. 3 lead:I would say best flashing
no. 4 lead: Surprisingly good, almost as good as 3.

Not very statistically accurate measuring technique.. video in the drive.. Tested also with higher rpm.. no drastically changes to flashing

Does this timing light test give any real information..

Since swapping the leads made no difference, I'd swap the spark plugs. I'm hoping that one or four is bad, and two or three (plug or lead) is half bad. But might as well test the resistance of the leads while at it anyway.

Saints wrote:Tested also for compression, 1 plug out at a time. All gave ~11 bar compression at normal throttle position and ~15 bar throttle fully opened. seems quite high (?).
no. 1 lead: Just occasional flashes.. 
no. 2 lead: flashing quite good.. kind of... half of the time

Does this timing light test give any real information..

Usually it's all plugs out to distribute engine cranking force optimally. Closed throttle gives inaccurate readings. Wide open throttle packs the cylinder with air for an accurate reading of compression power. Your engine's compression is classified as good in the BMW service manual that is downloadable from this site. It's full of news you can use.

The timing light is showing that spark is intermittent or of variable quality in cylinders #1 and #2; either condition must be remedied, so the light is useful in that regard, unless the timing light is faulty, too.  If the light is ok, the cause could be faulty spark plug leads and/or faulty plugs, as daveyson is indicating, unless it's something else.

I dont see that the leads have bene replaced.

Running HT leads on NGK plugs without the screw on bobbins destroys the inside of the cap on the lead and also is not good for the coil.

The ticking sound you are hearing is to my mind shorting of a coil or HT lead.

If the bike was run for a long time in this condition I would be suspecting both coil 2/3 and the leads for 2/3 as being the problem in which case swapping the coil AND with its plug leads would be necessary to see if it swaps over to cylinder 1/4.

In the opening post I listed new things. Bike had bad leads, because of nkg spark plugs being used without hats previously. They had arched a lot from the inside (now that i remember, two leads were especially bad, and two were bad but better, i spared the other pair.)

But now both the spark plugs and leads are NGK and new from tills.de. But i quess not new anymore, they have been used under 1 hour idling in neutral.

Saints wrote:But now both the spark plugs and leads are NGK and new from tills.de. But i quess not new anymore, they have been used under 1 hour idling in neutral.

Exactly. Maybe it is time to consider this option.

Doh got a bit lazy there. Another thing to try, unplug the tank, swap the black/red wire of the coil with the black/blue wire to see if that shifts the problem.