16-21 Yamaha XSR900 M4 Full Stainless System With RM1 Muffler
M4 Full Stainless System With RM1 Muffler Black ceramic coated RM1 style muffler 304 stainless steel tubing with high temp ceramic coating Saves 10 lbs over stock +8 hp over stock system Stock- 89db @ 5500rpm, M4- 105db @ 5500rpm Does not include quiet insert Stage 1 Q7 quiet insert sold separately