Motorbike Mike wrote:I seem to remember pointing toward the injectors on #4, #18 & #21. 

So you did 

The weird thing is that they didn't leak one drip of fuel when I had them out... I would have expected to see them leaking a LOT! But I will try it once again:M:

So I'm new to k bikes so this problem is fresh for me . All I can say is get your injectors cleaned properly . Run some petrol cleaner through a few tanks of fuel and make sure there's no water getting in . 
I had a weeks of problems similar to this and one of the issues was a injector working but not closing properly hence flooding the cyclinder. After taking them out and cleaning them and changing the o rings . I tested them under pressure and could see now they all looked like a similar spray pattern where as before one looked more powerful than the rest . 
Anyway I would put my money on injectors . Mine is running sweet now after a few bottles of petrol cleaner and a few hundred miles . 

Oh and just to mention I also had water in the fuel which got I through a leaking petrol cap on tank .

This recent thread shows that a faulty ECU can pump in too much fuel.  Perhaps your ECU hasn't failed completely but is on it's way out?

Yep. Starting to sound like the FICU is cactus. They're normally a very reliable unit but lately we've been seeing failures giving symptoms like excessive fuel at startup. Try swapping with a known good one. Just make sure its the correct one for the K100 2V as they aren't all the same. The K100 '83 to '90 uses #0 280 000 313

Similar issue here...
WTB FICU for 2V K100RS

Hi there!

Thought I might do a followup on what has been going on with My K-bike!

I had problems with an increasing oillevel and the oil smelling fr.o.m. fuel.

As you can see, if you have followed this thread, I've done some troubleshooting whitout any luck (Thank's for all advises anyway:tu1:).

Got a tip to check the microswitch in the trottlebody. Apparently it's supposed to click when you turn the throttle just a little bit -mine didn't!

Also noticed that the gaswire was a bit tight adjusted so the throttle would never get to a fully closed position. So I slackened the gaswire and adjusted the microswitch (is it called TPS?). Have ridden around 600km since this adjustment and doesn't experience any fuel in the oil anymore!

It seems like this was the cause of my problems. Perhaps someone knows if this is a plausible explanation?

Best regards
Jonas

Good to hear you're going well again. I cant figure out how that would cause the problem but strange things happen. It would however make it difficult to start.