Bike FitComfortable, Powerful and Fast
In these images, I demonstrate my current position on my TTX.
There are three key angles that must be maintained for proper efficiency. First, knee angle at full extension, which should be 143-150 degrees. Next, hip angle, for Ironman athletes this typically shouldn’t be any lower than 100 degrees. If your angle is well above 105 degrees, aerodynamics are causing you to lose precious time! Last, shoulder angle should be 80-90 degrees for proper skeletal support when riding on aerobars. Additonally, other factors such as aerobar pad placement and tilt need to be closely looked at.
I produce a pretty good amount of power, but a lot of my speed is from great position and proper equipment selection and bike set-up/build. I follow the F.I.S.T. methodology as detailed here: http://www.slowtwitch.com/Bike_Fit/index.html
I offer personalized TT/tri or road bike fitting for $100, which covers up to 2 hours of fit time. Cleat adjustments are included. Any parts needed to achieve the proper fit are extra.
Separate cleat fitting and shimming are also available for $10-20, including adjustment of pedal Q-factor, if needed. This works well if you have gotten new shoes, or new pedals, or if you are having knee pain, foot numbness, or notice your knees don’t track over your feet, the shoe/pedal interface needs to be evaluated. Shims/extenders are extra.
A Case Study:Typical fit from most bike stores....
An image of the bike store fit...
It doesn’t look all that fast, does it? It also wasn’t all that powerful or comfortable….
After some significant fit adjustments...
Much better, but still not perfect. This bike wasn’t the appropriate geometry. Note how low the seat post is, an indicator of a frame that is too large typically. A stem of 120mm was needed however, so the top tube length wasn’t too far off.
Ahhh, much better!
A change to a bike with a much longer reach and lower stack. Voila! A Comfortable, Powerful and Fast fit!