The shop lets me use the smallest they have which is a 100. The bike seems to ride fine with this size stem. If anything, the steering is slightly more relaxed. I have had a 120 on it for the past year.

Indolent58, I have changed my seat postion many times but finally settled into where it is now. I put it on a trainer yesterday and made sure the seat position was at the recommended reference position. My pedal axle to knee position is correct. Interestingly, my seat postion requires a slight setback post. I really like the bike and have 4900 miles on it. It is not uncomfortable. Just when I reach for the hoods, I am more comfortable holding on the bar at the base of the hoods than on top of the hoods themself. The hoods are at a standard position on the bars and the bars are in a pretty neutral rotation at the stem.

Michel, I can relate. I have not ridden a bunch of different sized bikes. But I ride with a friend that is my height and he rides a 58cm Cannondale. That size bike is way too short for my legs but the top tube length seemed pretty good. A 60 cm Trek 5200 may have been possible, but its top tube is only 11 mm shorter. That doesn't make that big of a difference. I think I am going to purchase a 100mm stem.

Tree, thanks. I have always looked at sizing as a reference for a place to start. I think a 90 stem would put the bar over the axle. I'll play around with the 100 and 120 more and see where to go.