Cockpit length vs. braaapablity

Hi Lee,
I keep hearing you say “….Longer is more XC-able; shorter is more braaapable and a longer bike with a shorter stem is a great compromise.” You said the same thing in your book! I believe you but I never really understand why. …

(Assuming we are talking about the same bike with same geometry but in a different size.)

XC-able –

If the seat angle remain the same, why do I need a longer cockpit for XC? How does a longer cockpit benefit me on climbs?

If we maintain the same effective cockpit length by altering the stem, is there any difference in XC ability between a large or medium size frame?

Braaapable –

If the wheel base remain the same, why a shorter stem makes it more braaapable?

If we were talking about handling, would a smaller bike with long stem & short wheelbase handle better or larger bikes with short stem but a long wheelbase handle better? And why?

Cheers, Chay.


Hey Chay.

– Longer cockpits (within reason) tend to aid seated pedaling because they 1) open up your upper body and 2) encourage you to rotate your torso and hips forward. These things tend to improve efficiency. You can learn to climb with a short cockpit, but most riders climb more powerfully with a longer one.

– Given the same wheelbase and/or cockpit length, shorter stems handle better (are more braaapable) than longer stems. 1) As you turn the bars, shorter stems have less side-to-side sway. 2) Shorter stems place the bars farther behind the front hub, which makes bikes feel better on fun terrain. It’s no accident that the more terrain-oriented a bike is, the farther its bars are behind the front hub. Check out this madness:



– Given the same cockpit length, a longer bike with a shorter stem is more braaapable than a shorter bike with a longer stem. Why:

1. Longer cockpits favor all-around riding.

2. Short stems handle better than long ones.

The longer wheelbase is a wash. It might slow down your handling, but it makes your bike more stable. I believe a good rider can rip on a bike of any length — as long as he has the right stem, body position and technique. Some downhillers and dirt jumpers prefer shorter wheelbases, but they tend to run longish top tubes and short stems.

I hope this makes sense.

Braaap!!!

— Lee


6 replies
  1. Chay says:

    Lee, that is why riders keep coming back to your web site…you have such a way to explain a complex idea in lay man terms.

    Large bike with short stem it is for my new Giant Reign!

    Thanks dude.

  2. Oso Negro says:

    Chay, if you haven’t yet purchased the Reign, ride both sizes you may be considering. I went from a XC 19.5″ to a Reign 20″ on advice from a LBS. No shorty stem could make it braap for me. I had to size down to the 18″ and still go with a 60mm stem. It’s full WFO braapomatic now, but I never would have thought I would go to a Med. frame being 6’1″. Ride what feels right. Cheers to Lee and good luck.

  3. Mike LaFlow says:

    Totally with Oso Negro.
    Ride It and you will Know.
    My partner & I have identical Stumpys, one XL & one Med.
    I ride both. Both fun, & very different.
    Med is quick in turns but I can change the front-back center of gravity by shifting my position an inch.
    Not always good.
    XL is much more forgiving, hence more stable & so I take more risks.
    Sometimes quite good.
    Different dimensions of braaaap.

  4. Thony says:

    Lee,

    I used to ride 16″ (center to top) ht xc bike and willing to move to turner flux. but unfortunately they only have 15″ (small) and 17″ (medium). do you think medium with shorter stem will fit me better than the small one? how short stem lenght should I use then?
    Thanks,
    th

  5. leelikesbikes says:

    Probably the medium with a very short stem, like 50mm.

    On your old bike, measure the vertical and horizontal distance between your bottom bracket and handlebars. If you like that setup, re-create it on your new bike.

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