The obvious will probably get noticed (this place is full of detectives) but until then I'm not going to say it...
...Bike had a small lie down after falling off side stand. I may or may not have (cos I don't recall but I figure I did) depressed front brake lever in the process of picking it up. I now have one rotor noticeably warmer than the other side and a less than solid brake lever. There is no indication of anything in the brake system, forks or axle having taken any of the impact.
I'm going to be captain obvious and say that I presume this means at a very basic level there's air in the system and that furthermore given one rotor is getting warmer (but not considerably hot) than the other that the air is sitting somewhere between the good (right side) calliper and the pistons in the left.
To be honest, and I'm only commuting currently so its not too bad (I'm not needing to scrub off huge speeds), its not super bad but there's obviously summit wrong. It will be due for a service in the near future and I will get the shop to look at it (cos frankly i've got lazy and don't want to get my hands dirty) however...
I'm wondering what the chances are (were) of getting air in the lines given the amount of fluid in the reservoir. Surely this would have been enough fluid to completely cover the entry hole to the master cylinder even when on its side so no air should/would have been sucked in.
What I expect I will get along with the Answer: