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I'm looking to purchase my first cyclocross bike and just found a good deal from someone. It's a Cannondale CAADX tiagra 2015 with a frame size of 56 cm (top tube 56cm basically). I'm a little bit afraid it might be too big for me. My height is 180 cm (5'11) with an inseam of 82 cm. Do you think it would be too big for me, especially on long rides?
From what I've read, it seems that a 54cm frame would be much better for me, but this is a real good deal.
I can't test the bike, because the guy lives in another city.