Yoshimura ZX-14R 12-23 Race R-77 Stainless Slip-On Exhaust, w/ Carbon Fiber MufflersYoshimura ZX 14R 12 23 Race R 77 Stainless Slip On Exhaust, W Carbon Fiber Mufflers The popular R 77 Slip On offers outstanding performance, thanks to being developed in the heat of competition. It features a trapezoidal design, which allows a large volume of packing material and in turn delivers top performance. The R 77 muffler's front cap is MIG welded, while the end cap is riveted using high end 304 L polished stainless steel rivets and bands.