Originally Posted by
mstateglfr
What is the reason for larger in front? I've seen a bunch of rigid frame and hardtail bikes withal fatter rear tire.
On my bike, first and foremost it's about clearance. Front tire measures as a 2.8, rear tire is just slightly wider than a 2.4 (wide rim).
Also, though, a slightly wider tire in the front is good because of traction. If your rear tire skids out, you'll probably be fine. If your front tire skids out, you're almost certainly going to crash.
I don't think anyone is using wider tires in the rear anymore.