The bike ran great during a 4500km trip. The last day the idle went up by 300 RPM and the engine was not starting as well as it did before, but still ran more or less okay. The next morning the bike ran like shown in the video... really bad and riding it is impossible. What causes this problem is unclear to me. Possibly a sensor or something that has gone on the blink? It seemes to me that fuel starvation may have something to do with it. 4500km ago a new fuel filter was installed.
---
Problem solved. It was a bad connection between the ECU and its connector. Just unplugged the connector, and plugged it back in. Bike runs just fine now