I went to the mechanic for the problem and after 3 days he returned the bike to me.
The tank and the petrol pump were completely clogged with mud.
I don't know how this is possible but I think it is due to the fact that the old owner left the bike stopping for months under the house without any foresight.
trying the bike I immediately noticed how much it has improved but already after a couple of days I notice that it is difficult to overcome the 9000 rpm ....
I had thought, but if I had mud in the tank, couldn't it be that it had circulated in the engine?
if the tank and the pump are clean ... what could I clean? my bike is injected.