The wifey and I went riding today in the scorching heat. She pulled up next to me and said her front brake wasn't working. We made our way back to the truck and suddenly it started working again. I went ahead and flushed the fluid anyways. Long story short, the front brake faded again, but would sometimes work. I guess the master cylinder went bad. I've never seen one intermittently fail/work. I don't believe it has air in it. I think it must be junk. Any ideas?