Just recently broke a crank on the fixie, a SRAM Omnium 165mm track crank. I had installed it on Feb 6, 2011, and it broke on Oct. 11 after 35,270 km. Yeah, I keep track of component life. It snapped suddenly right at the pedal. My right foot just continued straight down, and I crashed to the right, but there were no cars coming anyway. I was at low speed going up a hill, so I just banged my right knee, and it's pretty well healed now.
I haven't broken a crank since the 1970's, when I went thru about six of them over successive Vancouver winters. I started washing the grit and road salt off the cranks after each day of winter commuting, and I hadn't broken a crank since, until this last one. Usually, a crank weakened by winter salt will tend to break the next fall, but I'm pretty careful about washing the cranks during the winter. Anyway, good thing this didn't happen during an important ride, like a California Triple Crown double century after I'd flown down there!
I thought this might be related to the bike falling over onto the crank at some point previously, but the only times I can remember the bike falling onto the crank, it fell on the left side, and this was the right crank. Anyway, I think I will send SRAM a photo and see what they think. I was going to replace the crank anyway with a Rotor 3D with power meter and a Hollowtech bottom bracket (the most intelligent crank attachment I've seen for an external bb); I just didn't get around to it in time.
Here's the photo, taken at the side of the road just after I had picked myself up off the roadway:
Luis