I got the old airbox from an Austrian guy including the corresponding tank, the covering [or panel or trim] with the snorkeling, and the seat. Overall, a copy of Honda RC45. The air inlets in the panel go directly in the snorkel. The air stream enters through this, through the tank, directly into the airbox and supplies the engine with enough fresh air. At first it was very difficult to tune the carburettor on it.It took a lot of time and a lot of nerve. The system worked great on a racetrack, it was designed to get a lot of air into the airbox. In addition, I had a Lambda probe installed on the motorcycle to check what happens at high speeds. In fact , at a speed of over 200 km/h the motor wasted away. We could not simulate that on the test either.