Originally Posted by
milesf
Again, I'm quite new, but what's the reasoning for not running a significantly more aggressive tire in the rear than in the front? I know it would make for much more rolling resistance, but is there a reason other than that?
The majority of your weight when riding is on your back tire. Because of that you don't need a more aggressive tire on the back. You'll get the traction you need, not likely to wash out and smaller lugs = less rolling resistance and easier pedaling. Because the front wheel has less weight on it and is constantly being turned left and right a more aggressive tires minimizes the chances of washing out.
I run Continental Cross King in the back and Continental Trail King in the front.