https://www.yoshimura-rd.com/collecti...

An All-new Honda CRF450 calls for an all new exhaust from the ones that know it best. Over a year in development before its release, the new RS-12 is ready with a specially crafted rear muffler resonator, machined joint, PTF sound insert innovation and CAD designed hydroformed header, this exhaust is ready to win championships right out of the box!