I was on a 25 mile ride yesterday with three other riders. None of us had ridden them less than 4,000 miles. Two were on DF bikes and one on an HP Velotechnic Street Machine, I on my CT700. I asked them how many times they had replaced chains. The answer was zero for everybody. One DF rider has 14,000 miles on his DF bike. I know the guy on the HP Velo has thousands of miles on his. Maybe it is just a matter of riding in an area where it rarely rains. The desert does tend to be dusty, particularly when the wind is in the mid 20 mph range as it was yesterday.