All depends on what type of riding you do. I run a Hans Dampf front and Wolverine rear for my type of riding. Lots of fast descents with rocks and tires others have recommended like the SB8 and Crossmark I cut sidewalls on consistently. The Ardent works really well in the rear too. You could not get me to run any other tire other than the HD on the front now. Rear I have also run a Specialized Captain and really liked it. Very fast rolling and good grip.

For xc riding, I'd second SB8 for winter or other conditions with lots of hardpack. They really work way better than you'd ever expect from looking at the tread. I've also used Crossmark, it works well when things are looser, but right now I'm running Schwalbe's Racing Ralph in rear and Rocket Ron up front - been very pleased.

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