I want to get into mountain biking, but I don't have a proper mountain bike. What I do have is a hybrid bike with 700c wheels. Can I put some 29" knobby tires on my hybrid and make it into some sort of mountain bike on the cheap? This is my suspension fork, but how much MTB tire can I fit in it? And will it work turning a hybrid into a MTB with better tires, or should I just quit being dumb and fork out the money and get a real MTB?