ktm’s rc4 is actually more than a rumor. the austrian manufacturer let loose a prototype skinned in cagiva mito bodywork to lap an unspecified track along with the latest supersport bikes. they also let loose a rendering of the upcoming bike. the rc4 shares the same angular style as its big brother, the rc8, but power comes from a 654cc single from the venerable 690 duke. with a high power-to-weight ratio, the proto was lapping a couple seconds behind the 600’s. expect it to drop at the 2008 paris motorcycle show at the end of sept (the rc8 was revealed at the same show last year).