if its a fuel injected 955i i would change the fuel filter they are prone to blocking up on these bikes.it sounds like fuel starvation if it cuts out at higher revs so its a good chance its a blockage or a fault with the fuel system,i take it it has fresh petrol in it and not old stuff and that there is no water in the fuel system i.e the tank as these also have a problem with the small drain hole in the fuel tank cap well blocking up which causes a small pond to form in the cap well and it empties into the tank everytime you lift the tank cap up.
adam bike doctor
June 2010