I have done a few +80 rides on the fix. Comfort is an issue with track geometry. I keep trying to get some good miles in lately but without someone else to ride with I usually end up bored and quit at about 40. That's if I'm sticking to the paved bike trail. It's great to not have traffic and I can zone out with the ipod, but the scenery sucks and I think that has a lot to do with the boredom. If I don't stick to the trails, I get bored from not listening to music. I just need people to ride with and keep me motivated. I did manage 50 today because I was having such a great time at my usual turnaround point that I just kept going and exploring new routes.