
During
 traveling, the inside of the crankcase is pressurized by the high-speed
 reciprocating motion of the piston. This pressure builds and becomes a 
large resistance to the piston's movement, causing various harmful 
effects.
 The AELLA Crankcase Breather / internal 
pressure control valve keeps the crankcase's internal pressure 
optimized. This optimization has many positive effects on your 
motorcycle, such as: A reduction of vibration of the engine, A reduction
 of engine braking which is criticized as being too strong on the L-twin
 engines, and the entry of the corner becomes easier, with greater 
control. 
You can also experience the improvement of 
torque as it is smoothed and improved, as if you had a custom build/tune
 of the engine.
Compatible with all 4 cylinder MV Agusta models:
- F4 750/1000/R/312/etc...
 
- B4 Brutale 750/910/990/1090/etc...
 
Ram air pressurized bikes such as the F4 require separate blow-off valves