In this category you will find all the complete mufflers we can have for your YAMAHA 4 strokes like the YZF, WRF, WR F, YZ F,... We will propose you mufflers of the brand ART, YOSHIMURA, PRO CIRCUIT, CRD, SCORPION,... These exhaust lines include the collector as well as its silencer. A muffler is less important on a 4 stroke engine than on a 2 stroke engine. But often on the original machines they are not perfectly studied. A complete exhaust system allows you to save weight and performance on your engine. Often easy to install giving a racing look to the motocross bike.