I currently have an Orbea Aneto which is basically a flat bar road bike. It does have 135mm spacing in the rear, but for the most part, the components are road.

I am contemplating getting a new set of wheels, something a little more sturdy, and at the same time I am thinking of getting more of a mountain cassette like a Shimano Deore 9 speed 11-32. I currently have a Shimano Tiagra 9 speed and am wondering if the spacing is the same between the two.

Do you foresee any problems that I might have? I really like the idea of just swapping out the wheels when my trips go from road to trails.

Thanks.