TriRig's Pedal Shootout
Jul 29, 2012
article & images by Nick Salazar
It is generally-accepted cycling wisdom is that float can help prevent knee injury, the reasons for which are typically given as either 1) a rider's knee does not want to remain in a single plane while pedaling, or 2) movement of the foot allows a rider to keep their knee within a single plane while pedaling. The reasons seem rather different, but I suspect both are true to some extent. There isn't a ton of great literature studying the effects of pedal float, but there is a little, and it seems to corroborate the injury-prevention story.
And float has been around so long, people rarely question it. Most people don't see a need for an alternative, if they don't suffer knee problems. However, there are opponents to float, or rather, PROponents of fixed pedals. And these people aren't just fringe players or eccentrics. A young Texan named Lance Armstrong used fixed pedals throughout his career, and has suffered no knee injuries despite the very long, hard miles he spent on the way to his seven Tour victories. And he's just one example. I recently covered Tom Danielson correcting a foot issue, and it wasn't by floating his pedals. Tom controls for stance width, cleat position, and varus tilt. But the pedals stay fixed. And Tom goes fast.
So how do we reconcile the two? Why does float seem to work well for so many, yet not be necessary for some? Just blind luck of genetics? I think not. What fixed-pedal advocates often postulate, and I have come to believe, is that if your foot is in the proper place to begin with, you don't really need float. Your knee will fix in place, and your foot will not want to move around. I've experienced this myself. But the solution isn't merely to rotate your cleat.
Fixing the problem
There's another very important element to cleat fit, which is often ignored. And that's Q-factor. We address width in so many areas on our bike without hesitation: saddle geometry, handlebar width, pad stance, and even the gap between our shifters. But countless numbers of cyclists and triathletes slap on a set of cranks and pedals without once considering the geometric relationship they are going to create between their hips, knees, and feet. And it's this relationship that determines pedal comfort and efficienty, and the effectiveness of a fixed-pedal system.
As mentioned, I've experienced this myself. When I use pedals that float, if their Q-factor is too wide (for me, a total of 260mm between cranks and pedals), I end up with serious pain in my iliotibial band. Can't avoid it. On the other hand, when I drop down to 250mm or less, I don't need to float at all. And I much prefer the solid feeling of a fixed pedal, which just seems to want to take your power more than a floating pedal does.
Word to the Wise
Lest anyone get the wrong idea, I'm not saying that fixed pedals are the answer for everyone. I'm not even saying everyone should jump out and try it. What I'm saying, and what I believe is true, is that not enough people are paying attention to the right fit metrics, and that more people would be very happy in fixed pedals if they did pay attention to those metrics.
So how do you get that information? First and foremost, by getting the right bike fit. Fit systems including Retul and Specialized's BG Fit take a very good look at how your knee tracks through the pedal stroke, and attempt to improve alignment in a way that will minimize knee problems. If you're having alignment problems, a good fitter will often recommend a pedal swap to bring your feet either inward or outward, to get them better aligned under your knee. I've been to fits where the first question was "are you stuck with a pedal sponsor? Because we may need to bring your feet closer to the cranks."
And of course, the very best way to find out if fixed cleats suit you is to try them out. Even using the best analytical tools available, often the best way to determine if something works is to simply hit the road and put some miles in. But as always, a little education ahead of time can often help you make a better decision.
This was a long, fairly dense article. If you made it through to the end, I want to thank you for sticking with it, and hopefully the information helps you to be a little more prepared next time you are looking to pick up a pedal. And keep your eyes peeled for the little teaser I mentioned on the previous page.