Join Date: Jan 2006
Location: Bismarck, ND
Bikes: Modified Burley Koosah, Trek Navigater folding, downtube folding
I rode my bent for about a year then started to get sore knees. I talked to a guy named Mark Stonich at Bikesmith.com who makes custom shortened cranks. For some reasons bikes seem to come in all sizes but the cranks are all 175's or 170's.
I had already changed the front chain ring to gear it down because of weakeness following a back operation in the left knee, and by using Mark's shortened crank (152's) it worked out perfectly for me at least. i always had spun faster than everybody else anyway, and this just seemed to remedy the knee problem without losing any low end power because of my gearing down a bit.
There are also knee extenders that a friend uses and this works for him.
Whenever I ride behind a pack of bikers it never ceases to amaze me the huge variety of knees you see - pigeon toes, knock kneed, cowboy kneed, etc. So you could try a few of these mods to see if they help.
The more i ride the more i feel that a bike fit is a personal thing, and one size rarely fits all, nor does one mod or adjustment necessarily help the next rider. Bottom line, trial and error - if it feels good, do it!