Cornering: Why are their butts out?

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Lee,
I never thought I could learn so much from a book about mountain biking! My cornering has improved incredibly after reading (and re-reading countless times) the section on railing.

There’s something I’m trying to figure out, though. If you watch Andrew Shandro and others in The Collective and Roam you’ll see the riders cornering with their butts off to the outside of the turn. There seems to be more going on than just leaning the bike more than the body, but I can’t quite figure out the dynamics. What gives?
Harry

Hey Harry,

Two main things:

1. Leaning the bike more than the body. This increases cornering force and lets you stay balanced when the tires drift.

2. Turning your entire body into the turn. Driving from the hips adds power to the turn, increases space for your bike and orients you to the exit.




This is a ridiculous exaggeration, to expand my range of motion. I’m really good in a parking lot.

From her hips up, Bobbi Watt is aimed where she wants to go.

Me in the Santa Cruz Mountains. On a twisty singletrack, keep your upper body pointed down the trail, and let the bike handle the turns.

Peaty shows this concept in real-life, two-wheel-drifting DH action. Big Bear style.


Pulling 3Gs, Pump Track Nation Style. My whole body — no, my entire consciousness — is oriented toward the next set of rollers.
16 replies
  3. Harry says:

    Thanks for the reply, Lee! I guess it looks different in motion as opposed to seeing a still photograph. I kinda thought that’s what was going on but wasn’t quite sure. I surfed for many years; there’s a similar action when you’re cranking a hard turn. I do it on a bike when my body is leaning more than the bike, but just can’t get the hang of it when I’ve got my bike leaned over more than my bike. Practice, practice, practice…

  4. Stephen says:

    Lee,

    So I was sitting around with my brother the other day who is a physicist (read professional geek) watching e5. When we broke it down it did not seem like this particular position would have any physical advantage besides control on the flat sketchy goodness. It would seem that in berms you would want as much mass as possible at the center of the circle so as to decrease your rotational inertia and therefore increase cornering speed. According to this theory you would want to lean your body more then the bike. Now having ridden here for a while I know that riding as you described above is indeed the correct and fastest way to corner so I was just wondering how this can be explained physically. Maybe a leelikesdiagrams?

    peace,
    Stephen

  5. leelikesbikes says:

    A physicist — cool! I think I have the soul of a physicist, but the math skills of a liberal arts major …

    In a world with perfect traction, you definitely want your CG as close to the center of the circle as possible. You can get away with this on a paved BMX berm. The problem is, when your body is extended toward the inside of the turn, and you lose traction, there’s nothing to hold you up.

    Here are two advantages to leaning your bike more than your body:

    – When they tires slide (which they do all the time), you can stay balanced over the wheels and make corrections.

    – You can load your tires vertically. This is the secret to maximizing traction.

    Stay tuned for more on that action. Diagrams!

  7. Juan says:

    Hi Lee!this is Juan from Spain!, I bought your book time ago and I think it’s a good improvement for those intermediate riders who want to get better in some specific aspects involved in riding..as a result,your book has helped in many aspects of my riding!
    But I have one question to make (sorry for hijacking the post to the OP but in same ways is related to it..)…how can I cope with very tight turns in downhill, sometimes with steep turns full of rocks or roots?do you think countersteering is the best way to cope with these turns with my feet levelled??cheers!

  8. leelikesbikes says:

    Get low. Weight the outside pedal. Look through the turn. Lean your bike. Keep your hands neutral and let your bars turn naturally.

  9. Juan says:

    Lee, cheers for your reply….when you say weight the outside pedal, do I have to have my pedals levelled or the outside pedal down and the inside pedal up??cheers in advance!Juan.

  10. leelikesbikes says:

    If you can put all your weight on one pedal, and still keep your pedals level, that will be quite a trick.

    Outside pedal down.

  12. Chris says:

    Today I tried experimenting with using my butt as a rudder, as described and it did make a difference, especially on faster, tighter corners. I used to point into the turn, but now my whole spine is pointing into it, instead of from the waist up, or whatever I did before, I can’t remember! I instantly noticed the change. And I did notice it was a better stance when the tires were drifting.

    Thank you Harry. Thank you Lee. In one post and one ride, I ride better. What a great site.

  13. Jeff says:

    #2 “Turning your entire body into the turn.” This works so well for road biking as well. Turning my hips in the direction of the turn is the number one tip I received through the years–so much more control.

  15. Richard Powell says:

    I read Mastering Mtb a couple of years back and it gave me huge improvement in my cornering speed, skills and confidence.

    Recently I have been XC racing and seem to have fallen into bad habits again – doing stupid things like leaning further than the bike, tensing, picking bad lines, and not braking enough before turns.

    Are there any training drills I can do to sort this out quickly before the bad habits become ingrained?

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