Yo, ho, ho, the stem is out. Just like Salamandrine, I don't want to force it, because its the only one bike, I have. So i go to my work place with my bike - there is a very very long instrument for the bolt (i don''t know the word in english). Slowly with a minumum pressure - its free. There's not even a scratch. I used some very thick grease for motorcycle chain. The same i use for my chain.

Thank you for advices You are great!