Originally Posted by HammerTheHill

After thinking about why they would run v-brake in the back and front disc I have come to this conclusion. Most of a persons stopping power comes from the front brake. We learned this when we started driving, the front brakes wear quicker than the back ones due to the fact of momentum change, shifting towards the front. This is also applied to road cycling, I use my front brake more than the rear, better stopping power. So the reason of dirt jumpers using a front disc brake is that is where the majority of their stopping power is going to come from and since disc brakes have a better stopping ablility than v-brakes, they place it on the front. Now why they have a v-brake in the back, I can't explain. Maybe its the back up in case the disc fails or maybe they couldn't afford both front and rear disc's. Or the bike doesn't except disc brakes and only the front fork does, so they opted to go that route.