One of they ways they are attempting to do that is by using an external flywheel, as used by Ducati and, it is rumoured, Honda. By altering the mass of the external flywheel, you alter the character of the engine. Less weight, and the engine is more responsive, but a bit more aggressive. More weight, and the engine doesn’t accelerate as hard, but you get more progressive engine braking. Having an external flywheel means you can change it and adapt engine character to each individual circuit without breaking the engine seals. Engine braking is a key target for Aprilia, to help the bike enter corners better.