These velocity stacks we have developed for Aprilia RS 660/TUONO 660 are necessary to improve the air intake during the phases of opening the throttle control.
Due to the particular shape, this allows a reduction in air turbulence during the suction phase, improves the air intake from inside the air box, facilitates the intake and reduces the response time of the engine especially when you have a violent opening of the throttle.
The shape and length of the velocity stack has been studied by our design department to reconcile the engine at different engine speeds, to increase the suction strength and to improve the coverage at low engine speeds. The velocity stack is mounted inside the air box.

The velocity stacks have been designed within our company and produced from aircraft quality 7075 T6 aluminium using some of the most modern CNC machinery available.