In cooperation with several Yamaha teams and riders, Twin Air has developed a new Airbox Kit for the Yamaha YZF250/450.
The new Airbox Kit creates more open space within the airbox to optimize the airflow into your engine.
The bigger airbox then allows for a bigger air filter on the Twin Air Powerflow Kit.
In resources, you can find the Dyno testing reesults of the Airbox Kit compared to an OEM Yamaha filter, Twin Air standard replacement filter and a Twin Air Powerflow Kit tested on a standard 2017 YZF250.
As you can see in the results, the Airbox Kit (red line) gives you 0.78 more HP.
The Airbox Kit fits the 2014-2017 Yamaha YZF250 and 450 models. The Airbox Kit comes with a Big Air Filter, black Airbox lid, aluminium cage and sealing ring, air filter bolt, spacer and mounting hardware. The airbox kit is easy to install following the instruction guide.