Yamaha has implemented measures to optimize the auditory experience for riders on their new MT-09 naked models.
In adherence to Euro 5 regulations, which closely monitor and restrict noise emissions, the design of exhausts, intakes, and engine covers has been influenced to dampen undesirable (and desirable) sounds.
While the commitment to environmental responsibility is evident, the importance of the engine’s sound as a source of riding pleasure has always been part of the joy of riding, especially when dealing with a distinctive motor like the 890cc CP3 engine featured in Yamaha’s 2024 MT-09 naked range.
Recognizing that intake noise often holds equal allure to exhaust sound, Yamaha has introduced a patent-applied intake amplifier.
This innovative device directs the intake sound specifically towards the rider without escalating overall noise levels on the MT-09.
In reference to the 2024 model, Yamaha recently stated, “Following the Jin-Ki Kanno philosophy to stimulate the rider’s senses and make them feel at one with the bike, sound was an important consideration in the latest EU5+ CP3 engine”.
The new MT-09’s sound experience is enhanced by a modified airbox with two redesigned air-intake ducts, accentuating high-frequency sounds while maintaining a smooth throttle response.
To further emphasize this sound, especially at higher speeds and revs, Yamaha has introduced a novel acoustic amplifier grille atop the bike. This component, subject to a patent application, serves as the key element in the system. Visually, it’s discreetly integrated into the bike’s design, with a plastic cover surrounding the fuel filler and extending to the ignition key, featuring two metal grilles resembling speaker covers.
Contrary to expectations, these grilles are not housing speakers. Instead, they represent visible exits for a complex passage that leads directly to an opening in the airbox’s top side. This design enables the noise from the intake to be channeled upward through the grilles toward the rider without increasing the overall volume.
A critical aspect of this design involves preventing water from reaching the airbox through the grilles. Yamaha achieves this by extending a thin section of the fuel tank forward, in front of the fuel filler, creating a barrier between the grilles and the airbox intake.
This allows sound to travel forward and around this shielding section, reaching the grilles, while water entering through the grilles is directed forward over the tank and then downward through an opening at the front, avoiding contact with the airbox.
The thickness of the shielding is finely tuned to absorb certain frequencies, enhancing the overall quality of the noise emitted through the grilles. Yamaha’s attention to detail in the MT-09’s air intake amplifier underscores their commitment to providing riders with an enriched auditory experience while maintaining compliance with regulatory standards.