Yoshimura MT-10 22-25 AT2 Stainless Slip-On Exhaust, W/ Stainless MufflerYoshimura MT 10 22 25 AT2 Stainless Slip On Exhaust, W Stainless Muffler The powerful CP4 crossplane engine used in the Yamaha R1 also powers the MT 10. That makes this hyper naked bike scream with excitement, making it an easy target for us here at Yoshimura R&D. We utilized our Works Finish AT2 muffler with carbon fiber heel guard that compliments the design of the MT 10. Available in two options: AT2 Race Series 3 4 system (eliminates the CAT using