^ +1
Use the money you save on the conversion for new tires. Will you be riding in the snow? If so, get some of the biggest tires that'll fit.
Is that crank set a double? If so put a MTB bash guard on it. They are meant for off road riding to protect your chain rings, but they serve an extra purpose of protecting your trouser leg from getting stuck in the chain.

Also, MTB's look much better with bash guards