And why they don't work ~
(Plus, one system that does)
Essentially, there are four different fitting systems in use. This page describes them and points out their advantages and flaws.
Trial and error ~
The advantage of this system is that a rider feels in control of his own destiny. Though the most common method of bike fitting, Kyle has proven countless times that this system does not work. After 30 years of testing, Kyle can count on 1 hand the number of top pros that have settled into a fit that matches their body build! The overwhelming majority of riders, pros and amateurs alike, that attempt to maximize their fit by this method spend years carefully fine tuning a fit that is in the wrong ballpark!
By the eye ~
A conscientious and experienced bike pro can make a fine show with this method and build some confidence in a rider. Unfortunately, it's very easy to prove that this system does not work. After finding "your best fit" by this method ride for several weeks then move your saddle, etc to different positions. Now, go to some other eyeballing specialist or even the same one and go through the fitting procedure again. You'll find that you now have a very different fit from the first time! Of course, they can't both be right. It's highly unlikely either is correct. After decades of working with the finest riders from around the world, Kyle has developed one of the best eyeballs in the country and even he cannot do a proper fit by this method. Top quality fits are done within 5mm tolerances. No eye, not even Kyle's, can get close to the accuracy needed.
Power Optimization ~
At first glance, power optimization seems to make good sense. If we use a power reading machine then yes, we can find the position that currently gives you your most efficient ride. Unfortunately, it's only reading your current development. And as nearly all current development has been achieved by hit-or-miss, there is no reason to suspect that your current development is the best for your body. Power development is only useful to make very small adjustments AFTER an extended time in the position that is most efficient for your body to develop properly.
By the measurements ~
Muscle development on the bike is maximized by optimum use of the leverage dictated by your bone structure! So yes, body measurements are surely the one true means of finding your optimum fit. Unfortunately, nearly all measurement systems take their measurements from the wrong parts of your body; Kyle has extensively tested them all. For example, inseam measurements tell NOTHING about accurate saddle positioning for maximum muscle development. If someone is trying to fit your bike from your inseam measurement then it's time to move on.
30 years ago, after exhaustive testing of the prevailing measurement systems, Kyle recognized that they just didn't work! They took measurements from the wrong body parts and extended these faulty measurements to come up with fit positions that were even less accurate than eyeballs! That is when Kyle began his decades of testing to determine the wheres-and-hows of a perfect bike fit. Now, with the feedback of more than 8000 custom fits, Kyle can confidently tell you that his exclusive fitting system delivers results that no others come close to. But don't take our word for it. Click here to read hundreds of unsolicited responses to Kyle's legendary fit: Feedback