For the past two summers, I've been riding my bike using toe clips. I recently amped up the weekly distance to 100+ miles. On each ride, I began to feel a slight pain in my left knee after about 20 miles. Last week, as my trusty hybrid Schwinn SuperSport bike was in the shop for some routine maintenance, I stopped in Blue Sky Bicycles, a local cycling specialty store, to do a little window shopping.
I ended up in a very informative conversation with Jeff Cimino, a Former Expert level NORBA Racer, who has 15 years of experience in the bicycle industry. He showed me a road bike by Specialized that was, in effect, made for transitioning to the forward leaning road bike profile, but with a little height added to the handlebars. I bought the Specialized Sequoia Elite, because it allowed for riding in the dropped position or in an upright position that was slightly less bent over than the more racing oriented road bikes.
Jeff explained the benefits of cleated bike shoes and "clipless" pedals (read more on clipless pedals from the About.com Bicycling Guide) and convinced me to try the bike using clipless peddles. I immediately felt the difference of being "connected" to the bike, with a full transfer of power to the pedals completely through the cycling revolution.
Jeff continued through a complete fit up of seat and bar adjustment using levels and lasers to check foot placement and vertical knee alignment. As I was dialed in on the bike, cycling in position, it became apparent to Jeff that my knees were doing some funky motions during the pedaling revolutions.
When I was leaning forward and pedaling I didn't notice this much, because there a little play built into the shoe/pedal connection, but Jeff was sure that, over distance and time, I would feel this in my knee joints. This was also probably the cause of my pain when using the toe clips at distance.
In effect, the problem was the same as the issue I had with my ski boots - flexing my knee with my foot restrained caused my knee to roll outward off the vertical. My ski bootfitter straightened me up, and I now wondered whether it could it be done for my bike stroke, too? The answer was absolutely - in the hands of an expert a Rotational Adjustment Device (RAD) put the stoke in my biking stroke using the same principles as a ski bootfitter.
Bike Fitting and RAD Fitting
At Blue Sky Bicycles, as at most serious bike shops, when you purchase a bike there is a fitting procedure where you are first determined to fit a certain size bike frame based on your general body size. Then, the trained staff makes further adjustments in height and handlebar placements that are allowed in the play of each bike.
One of the fitting steps is a vertical plumb check that uses an plumb bob or, as at Blue Sky Bicycles, a laser setup to adjust the cleat setting to the relation of your knee/forefoot plumb. It was during the pedaling for this check that Jeff noticed, looking from the front of the bike, that my knees were not over my feet through the entire pedal cycle, with the left knee misalignment more pronounced than the right.
Since my feet were connected to the bike with the cleated biking shoes, my knees were, in effect, straining to move my feet to be where my usual gait accommodated it. This strain was what caused the pain when riding my hybrid bike with the tightened toe clips. The misalignment needed to be adjusted out or, multiplied by thousand of pedal cycles, would be bound to cause more pain and eventually some possible physical injury to my knee.
The biking shoe cleats can be tweaked off the "perfect" center line to compensate for misalignment and this is where the Rotational Adjustment Device (RAD) is used to bring the foot into alignment. The procedure involves temporarily replacing the pedals with the RADs, which, as you can see in the photo, have two wands.
One stationary wand shows the pedal axis and the other, movable wand, indicates the natural float of the foot as it passes through the pedal cycle. The trained fitter watches the pedaling and makes periodic adjustments until the foot flows through the cycle with the floating arm staying aligned with the stationary arm.
The Custom Aligned Bike Shoe
The finished product of the RAD fitting is that the cleats on my bike shoes are personalized to allow my normal gait to follow through on each of the countless pedal cycles. As you can see from the photo of the bottom of my bike shoes, the cleats have been tuned to pretty far off the center line of the shoe to get into alignment.
In effect, this translates roughly to the degrees of canting necessary on my ski boots to keep my boots flat - or aligned - to the snow plane. It also has the beneficial function of keeping my knees from severe over-straining and preserving them for the long winter on skis.
Is the RAD Fit for You?
If you have no trouble with your cycling gait or if you are sure you don't need any orthodic ski boot work, you probably don't need a RAD fitting and if you like toe clips use them. However, if you decide to try clipless pedals for the increase in power by being fully connected to the bike, be sure the tech does a visual for any misalignment.
The bottom line is that a RAD fitting is a service, so expect to pay for it. If you buy a bike, bike shoes, and clipless pedals online, and you have had corrective work done on your ski boots, I suggest you go to a biking specialty store and pay for a RAD fitting. You will not only find your biking is more fun but you can be confident you are saving wear and tear on your knees.