. . . It's LOONEY George Clooney, raging and cursing like a Hell's Angel wanna-be at the motorcycle shop where he bought his $56,000 customized Indian -- actually KICKING his bike and screaming at shocked customers: "THESE EFF-ING BIKES ARE NO EFF-ING GOOD!!" Months ago I scooped that generous George bought six Indians for himself and pals -- but he's howling because his bike's needed repairs a whopping 19 times! Complaining about oil leaks and a bum suspension, the star shouted: "This eff-ing bike's a piece of s--t! Why don't you just FIX the eff-ing thing, already?!" When he spotted a couple starting paperwork for a purchase, George bellowed, "Do yourself a favor . . . RIP UP that eff-ing application. You don't want to buy one of these eff-ing bikes!" The horrified would-be buyers split -- and left George screaming at mechanics!