A company in the UK called Roton Engine Developments made some progress in 2005 with a 2 rotor (one for inlet and one for exhaust) on a motorcycle single cylinder Husaberg. They filed patents and got an example running in 2006 but were backed by MG Rover who subsequently went bust, leaving Roton without enough funds to continue. The designs surfaced some years later in Australia with Engine Developments Australia Pty Ltd. A prototype casting was produced in 2013 on a Kawasaki Ninja 300 parallel twin unit. This unit is still in development phase at the time of writing but is significant as it has the potential to run much higher compression ratios than even other rotary valve engines due to a significant but undisclosed new cooling method of the combustion chamber and the ability to eliminate the throttle completely, making it vastly more economical at lower engine speeds, so it is claimed.