thanks for your replies!

I already checked the tyre pressure, and as you asumed, it was to high.

You mentioned, that I have to controll the steering wheel, this was the case before adjusting the tire pressure, before it was scaring! the steering wheel was moving!! don't now if there is a connection betwen pressure and this phaenomenon? do you?

regarding the torque of the wheels screewing this is something I need to check

any other advice?

to you know cases where there was a connection between vibrations at high speed and clutch wear?

thanks