First ride out today after the lock down, ended prematurely as the rear brake on the 2018 monster 1200 quit. It worked fine when put into the garage in November but not today! Pedal goes all the way to the exhaust with finger pressure. There is no sign of fluid loss, any ideas? I am tempted to bleed it but why would this happen? It is not that it is spongy it just does not exist. Presumably caused by air in the system or master cylinder seal failure?