Understand the Center of Mass for Mountain Bike Racers

Series Summary

Those of you who consider a dirt driveway to be off-road cycling need not read further. You obviously got your mountain bike just because it looks cool and eases over the speed bumps in your neighborhood. No, this sequence of videos is for the serious biker who would rather challenge a mountain than roll down a hill. If find yourself ten feet in the air thinking about how you could get higher for the next jump, these videos target you. If you refuse to get off of your bike at a creek crossing until the water level reaches above your head, you are indeed a serious mountain biker and can make good use of the advanced techniques explained in these clips.

Our mountain biking expert discusses the correct way to get over, around and through any obstacles you may encounter on your adventures. He also demonstrates proper weight distribution and riding techniques, and discusses modulation and braking theory. If these topics sound sophisticated, that's because they are, a veritable master's class in mountain biking physics. So get your degree today!

Video Transcript

"Unlike most other vehicles that you have probably have experience operating, you weigh a lot more than your bicycle. Because of that, your center of mass, or your center of gravity as it's commonly referred to, is really important to the way the bicycle, the way the bicycle rides, and the way it responds to your inputs. The thing about your own center of gravity is me standing here right now, if I dropped a line, a counter balanced line down from my belly, it'll basically just be sort of right down here below me. You can almost see it visually. If I go like this, which is pretty close to the optimal mountain biking position, what we call the attack position, my center of gravity sort of comes right down to my sternum straight to the ground. We want to try to apply that same sort of concept when we're riding a bike. I'm on my bike. If I'm just sitting bolt up right like this when I'm trying to climb a hill, you drop down that center of mass that's over here around the cranks and everything like that, and there's no weight on the front wheel. The front wheel wanders and lifts up and stuff like that. Same sort of thing if I'm sitting way over the front of the bike when I'm descending. The bike's going straight. My center of mass is front of that axle right there and the bike's going to handle real bad. I'm not going to be able to turn it, I'm not going to be able to slow it down. Instead what you want to do is you want to assume that same sort of position that I was talking about. Nice and low, and crunched."