A lot of work goes into the design of a motorcycle exhaust because riding as a hobby and sport is as much about the auditory experience as it is about the ride. In the case of the 2021 Yamaha MT-09, extensive work went into the design of the under-slung exhaust that replaced the side exit unit of the previous generation.

The redesigned exhaust on the 2021 MT-09 has to comply with Euro 5 emissions regulations whilst still turning in performance and for some riders, a pleasing exhaust note without being obnoxiously loud. For this, the Yamaha engineers made an exhaust chamber that reduces the 3-into-1 header into twin exhaust pipes.

This is combined with extensive engine noise reduction, notably in the gears which are machined to a closer tolerance. Under Euro 5, noise is also considered an emission, and this reduces the total amount of overall noise generated by the MT-09.

On the intake side of things, three inlet pipes let the 899 cc CP3 suck in air in adequate amounts and provide a pleasing intake sound while still being regulation compliant. The three pipes are of differing lengths and diameters, with Yamaha engineers taking inspiration from a church organ.

Launched in late October, the 2021 Yamaha MT-09 has been extensively reworked over the previous model. The CP3 inline three-cylinder now displaces 899 cc with a power output of 117.3 hp at 10,000 rpm and 93 Nm of torque at 7,000 rpm.

Weight has been reduced from 193 kg to 189 kg and an all-new frame is 2.3 kg lighter than before. Also new is a full-colour TFT-LCD instrument panel, LED lighting front and rear and adjustable front forks.