2011 Cannondale Carbon Synapse (Ultegra 6800 11-spd), 2009 Blue CXC
What model year? What wheelset is on the bike?
The 2014's are clinchers and come with the Versa Corsa Wheelset. It's hard to find any information on the Vera Corsa wheelset, but it seems to be the same wheelset that comes on the sportif and some of their other entry level road bikes, which makes me think that it's probably made for 32mm clincher maximum.
What are you planning to use this bike for? It should have come with 32mm stock clinchers.