It has been long since I have felt same time so stupid and so happy as now. I think I solved my throttle issue. I think it was that pdf Inge linked that finally made my slow mind click. I started to think that throttle worked perfectly last autumn. After that I have done nothing to the down end of the cable, but I have changed the handlebars twice and rerouted the upper end of the cable once more.
Before I thought that stickness can be cured only from the throttle lever, but now I have noticed that snapping the throttle bar makes the same effect. So 1+1 I suddenly was sure that the problem is not down end of cable, but upper end.
And it seems that I was right! I have been so stupid that I did not understand that under that rubbery thing (
http://kotisivu.dnainternet.net/ajk73/IP.jpg partly behind the mirror) was not just cable but also the adjustment system for throttle free play. And here helped pics of the pdf that Inge linked. I do have thet new cable (I think it was renewed at 2009).
I simply had too little freeplay on the throttle. Now with less wide handlebars it effected more on the system. I adjusted that freeplay and now the throttle works much smoother and does not stick at all. So no need for new cable!
Someone more tech oriented would have fixed this in minutes. For me it took about six months. But hey. Now it is fixed.
Thanks everyone for helping, hope this helps some others strugling with same kind of issues. Special thanks to Inge K.
It was so nice drive today with smooth operating throttle.
Edit: After longer run I am more confident of this really fixing the problem. Throttle feels better and works perfect!
Edit2: And after another run K100 slapped me in the face again. It ain't fixed but it is better. I think the metal upper parts are just so worn that occasionaly the cableholder system (the thing with litle chain and stuff) gets in wrong position and stucks. There are marks on that casing showing that it is worn. Positively now if it stucks it just makes throttle very sticky, but it does not jam it, so it won't affect on the idle revs anymore. So I just have to live with it I guess.