MTB Crank on a Cyclocross Bicycle? I have a new FELT Cyclocross frame and i am looking for a BB30 Crank to go with it.
I don't really need more more than one chainring, so i end up looking at a lo9t of MTB cranks on eBay.

What are the CONS of putting a MTB crank on my Cyclocross Bike?
Any known Problems?
There may be something that I don't know about, but if the crank fits on the bottom bracket, and if the chainring is reasonably close to the position of a middle ring on a triple chainring setup, then your chain line should be fine and everything should work. A lot of bike targeted at young riders have a single front ring and 7 or 8 gears in the back. 

The chain line is the most important thing to consider, since you don't want excessive torque on the chain when you are in either the lowest or highest gear.