Originally Posted by
geepondy
Yeah I posted quite a bit about it in another thread. I'm 5'10" and I tried a 56 cm Roubaix and a 54 cm Roubaix Sport. The 54 put me in a more upright postion which I liked and not that much more aggressive stance meaning the seat adjustment was not that much more higher than the handlebars for the 54 over the 56. I definitely like being more upright. But everyone I talk with seems to think at my height I should go with a 56 cm. I spoke with a professional bike fitter at a different shop and he says no way he would fit me on a 54. But as he mentioned there also is a lot of variances between the different bikes.
If choosing the 56cm Roubaix I'm saving $600 but giving up better wheels and going down to Tiagra vs 105.
I'm about 1/2" taller than you. I ride a 56 Roubaix. You can definitely change stems, but you need a Specialized "FutureStem".
On my Creo (similar frame with slightly longer wheelbase) I test rode both the 54 (M) and 56 (L). The 54 felt a little twitchy to me. I think I could probably have gotten used to it, but decided to go with the 56.
I previously rode a 56cm Diverge in 56. This was my first road bike. When I got a fit done, we went with a 90mm stem. When I got the Roubaix I assumed I'd end up doing the same, but maybe after a year of riding the bike I got more flexible or something. I never felt the need to shorten the stem on the Roubaix.