Just saw this post. I have a 2014 Bosanova and run 35mm Schwalbe Marathons. They just fit (had to flip the rear fender stay to keep them from rubbing.) There's no way I would have gotten 38s on but the 35s are wonderful, especially after those lousy Vittoria stock tires.

I run Gatorskins on my Cannondale tandem and love those for 50-100mi country rides on good pavement, but for my in-town Bosanova the Marathons give me much more versatility when I have a bit of off road or gravel riding.