Motorhead will be among those performing at the Mayhem Festival July 1, 2012 at the Shoreline Ampitheatre in Mountain View, CA. Festival starts at 1pm. Other bands headlining are Slipknot, Slayer and Anthrax. For a full lineup of all the bands performing, click on the link above and check out tour dates here. In the meantime, here's a performance of Motorhead doing Ace of Spades earlier this year.