Originally Posted by daotan
Assuming the wheels fit in the frame, will I be able to use my roadbike brakes?
First hurdle is wheel diameter. Given the different diameters the (most common) MTB rim brake surface would end up more than one inch away from where the(most common) Road rim brake surface would be.
The odds that the road brakes would actually be able to reach the MTB rims are poor.
I've seen a guy using home-made brake arm extenders, but I'd worry about the actual pinching power one would be able to generate with that.
Next hurdle is hub width, but I'd expect that wouldn't be critical. First, frames are flexible and will readily handle a little mismatch. Secondly, (rear) hubs usually comes with a few spacers thet can be tinkered with to create custom widths if needed.