I had a 'closer to God" moment a few years ago, while traveling at 110 kph on the superslab in Quebec.... all going well, hadn't used either brake in some time.....all of a sudden, the front brakes seized completely, the bike slowed on it's own, from highway speed to a complete stop in no more than 15 seconds, I had no idea what was happening (my buddy following thought I had blown the motor, all he could see was white smoke)...as luck would have it, I managed to get the bike stopped in a small traffic island, formed where an access road joined the highway, very nearly dumping it in the process. The brakes were completely locked, two of us could not push it to the shoulder of the road. So we waited, for about 20 minutes, while traffic wized by on the highway on one side and the entry road on the other.
Eventually, the calipers, rotors, and fluid cooled down enough so that the bike would move with both of us pushing, and we got it on the side of the road. Then I looked for the cause. Turns out there was no play at all in the front brake lever, the bolt adjuster was in constant contact with the hydraulic plunger. The locknut had apparently come loose, and over the course of the morning the bolt had gradually worked it's way forward, effectively applying the brakes without the lever being pulled. Eventually the heat generated by the stuck calipers/rotors had heated and expanded the brake fluid, eventually traveling back to the master cylinder, and siezing everything up.
After adjusting and LOCKING the lock nut in it's proper position (to allow a bit of clearance before the bolt hits the piston), the brakes worked fine, and I haven't had any problems since. However, I do find myself checking the lever for free play every once in a while, while riding the bike.
Cheers!
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