How tos, MTB 101 - Skills »
Cross country bike skills: rear wheel tracking
Editor’s note: This is the third in Ashwin’s series of cross country biking skills. The second discussed the trackstand, and the first introduced some basic concepts about bike handling. These pieces have a cool, old-school feel to them — I hope you’re enjoying them as much as I am.
The Problem
Tell me if you have every experienced this? Huffing and puffing up a single track hill, at your limit. You spy a rock in the trail. Deftly, you steer around it, pleased with yourself for missing it. Then your rear wheel hits the rock and you stall because you have so little speed and momentum, and you unclip.
The Skill
One of my favorite little skills is based on the knowledge of how your rear wheel tracks your front wheel when it is steered. This is one of those slow speed situations that is much different than the typical cornering/turning you do on a bicycle. For the most part we lean the bike to go around corners, but at slow speeds (under 8mph or so) we have to do some steering. It’s a common perception that the rear wheel tracks directly behind the front wheel. This is true when going in a straight line but changes drastically when the front wheel is steered.
The easiest way to illustrate this to yourself, is to wet down a section of your driveway with a hose. Roll your bicycle through water to get the wheels wet and then start riding or pushing the bike in a straight line. Steer the wheel one direction and then straighten out. Stop and check out the tracks made by the tires. You’ll see that the rear wheel tracks to the inside of the front wheel.
Typically, what happens when you hit that rock in the trail with your rear wheel, is that you steer around the rock with your front wheel just enough to miss it with the front tire. When you straighten out the front wheel, your rear usually is going straight for the rock. See the below series of pictures. (*Note that I am not following my own advice and am looking down. Do as I say, not as I do.)
How to do it
The trick to missing the rock with both wheels, is to steer much sharper around the rock with your front wheel before you straighten out. This forces the rear wheel to track to the inside of the rock and it will end up going by the side of the rock when you straighten out.
View this move from the side. (.mpg, 760kb)
To practice this, find something that is easy to ride over, like a small piece of wood or flat orange cone. Or something that will move like a tennis ball.
On the trail you’ll have to gauge how much track you have to work with in order to steer sharp enough and wide enough to miss an obstacle. This technique works especially well on a switch back because the trail is going in the direction you are steering.
Conclusion
This little trick comes in really handy in a lot of XC situations where your speeds are slow enough to require steering the front wheel. Hopefully it will save you from having to put a foot down and dab.