When riding back in MD we found this spot where there was a large stone (over hbar height) with a slope to it. However, the run up to it had a down slope to it. I noticed that I had a lot of difficulty just pulling up the fornt end when doing a pedal up. So I would usually pull up too late and just smack into it w/o getting any height. I wonder if this problem becomes even worse on a longer bike like a Koxx.