The Yamaha R6 and the Aprilia Tuono V4R, two motorcycles that have the ability to entertain, scare and mystify even the most hardened rider when it comes to performance. The R6 is a scalpel of a machine that has the ability to carve up corners with the precision of a surgeon. The Tuono V4R on the other hand is a blunt instrument that while capable, is more interested in sky high wheelies and hooliganism. Wes Siler and Isle of Man TT rider Jamie Robinson recently took to the canyons of Southern California to see which machine was more fun. Click through and check it out.