One of the challenges with trying to use a road bike as a cross bike is room for bigger tires. If you look at your bike, do you have room for knobby tires? Need to check space around the fork, brakes, seat stays, seat post, and chain stays. If you're running 23 or 25mm tires and space is already tight, you'd be hard pressed to fit 33 or 35mm tires in there.


If you have ample space, then you could put something beefier in there. The geometry wouldn't be ideal, but it'd be usable.