There is a known defect with all MV Agusta Motorcycles whereby the rear brake fails to operate in a normal fashion due to air getting into the brake system. The result is a "squishy" rear brake that does not activate the rear brake. End result is non-functioning rear brake. This puts the rider in a dangerous situation where they may not be able to brake in time to prevent an accident or full stop when needed. The problem is well known and documented by MV Agusta. My vehicle has been into the authorized dealer to rectify the problem 3 times, currently in the service center for the 4th time for this issue. There are no warnings indicating the braking system is malfunctioning.