Yoshimura R1200GS/R1250GS 13-22 R-77 Stainless Slip-On Exhaust, w/ Stainless MufflerYoshimura R1200GS R1250GS 13 22 R 77 Stainless Slip On Exhaust, w Stainless Muffler The BMW R 1250 GS is a beautiful adventure machine that claims 136HP and 105 ft. pounds of torque in stock form. We decided to add to the excitement of the 1250 boxer engine. Using our Works Finish R 77 profile muffler we developed a slip on that adds 1. 4 % peak HP and 1. 5% peak torque. These improvements not only make this beautiful BMW more fun to ride, our R 77