Gilbert Gilby J Clarke born August 17 1962 is an American musician singer songwriter and record producer best known for a 3year tenure as the rhythm guitarist of Guns N Roses replacing Izzy Stradlin in 1991 during the Use Your Illusion Tour Following his departure from the group Clarke went on to forge a solo career as well playing guitar with Slashs Snakepit Kat Men Heart Nancy Sinatra Kathy Valentine of the GoGos MC5 and forming his own group Rock Star Supernova with members of Metallica and Mötley Crüe Clarkes production work includes albums by LA Guns Bullets and Octane The Bronx and Vains of Jenna