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tbushnel
06-13-2005, 11:10 AM
I have used Speedplay X1 pedals for over a year on my road bike and at times on my touring bike. My overall cycling experience is limited to the last 3 years and my mileage was quite meager until this year (<1000/year). I now average 100 miles or more per week, which has been arrived at rather slowly over the last 6 months or so. Now, to the topic at hand.
I have always assumed that more float was better, and when I had some minor knee pain long ago I figured Speedplay would save me so I got frogs and X1s. Seemed comfy at first, but when my mileage began to pick up this year I had Knee pain, primarily on the left and mostly on the medial aspect of the knee. I had some older (90's) Look pedals sitting around that came on a bike I bought second hand and I tried them. AMAZING difference.
I had some pain already in my left knee but I went for a ride anyway and 2 things were obvious right away. First my pain was not aggravated and my pedaling felt good. Second I felt like I had a more powerful stroke with more of my effort going to turning the wheels, this even while riding "easily" given my already sore knee. Over the next 400 miles (3-4 weeks) I have had continued comfort and my knee pain has gone away.
Anyone have similar experiences? Can anyone comment on the float of Look pedals versus Speedplay Zeros? I really like the double sided entry of Speedplay, so when its time for new pedals I would be interested in Speedplay if I could limit my float enough.
Thanks for any comments.
Ted,

Bradford
06-13-2005, 12:01 PM
I am not a knee expert, I just have really bad knees. I used to think free float is always the answer, but after reading several posts like yours over the year, I've come to the conclusion that free float is the answer for some problems but does not work for others.

I went to Speedplays in 1995 and was an instant convert. Frogs are the best for my knees, but the lolipops are pretty good. I'll never go back to anything else because they work for me. I'm guessing that what is wrong with my knees is different from what is wrong with your knees, so the different pedals solve the problem.

I've moved from being a speedplay zelot to thinking blanket statements about pedals makes no sense at all. I guess it's different pedal stroks for different folks.

christian
06-13-2005, 12:11 PM
It may well be the pedals, and the change would tend to point in that direction, but from your description, it sounds a bit like illiotibial band pain. I've only ever suffered from that when drastically increasing mileage or effort (eg 53x19 hill repeats). Typically, I've found relief by dropping mileage for 4-5 days, and icing the knees.

I'd try that for the next few days, while you digest all the advice you're likely to get in this thread.

- Christian

Orin
06-13-2005, 01:10 PM
I have always assumed that more float was better, and when I had some minor knee pain long ago I figured Speedplay would save me so I got frogs and X1s. Seemed comfy at first, but when my mileage began to pick up this year I had Knee pain, primarily on the left and mostly on the medial aspect of the knee.
<SNIP>
Anyone have similar experiences? Can anyone comment on the float of Look pedals versus Speedplay Zeros? I really like the double sided entry of Speedplay, so when its time for new pedals I would be interested in Speedplay if I could limit my float enough.
Thanks for any comments.
Ted,

I had the same problem. In my case, it seemed to be caused by over-pronation - my foot would collapse and rotate my lower leg, putting pressure on the inside of the knee. Superfeet insoles (green) helped a lot. I switched to Speedplay Zeros set to prevent heel-in rotation and that worked... I'm now on my second set of cleats for them, though this time, I havn't limited the float yet - still using the Superfeet insoles though - and I haven't had the medial pain with this combination.

Orin.

Ti Designs
06-13-2005, 02:06 PM
It ain't all about the knee(s). You can look at the pedal stroke from one of two directions, hip down or pedal up. From hip down (from point of power) the lateral orbit is based on the direction the hip faces - and it's not always forward. If it's nor forward you have the case where the rest of the leg moves away from the centerline of the bike with extension and closer to the centerline at the back of the pedal stroke. I've never seen a bottom bracket with a universal joint built in, so that has to be taken up somehow. In theory a pedal system with float can take up the lateral distance, but in watching people pedal I've never seen it happen. Past the hip orbit we get to the knee. The knee is a complicated pivot point, having a floating structure and lots of cables attached pulling and restricting in various directions. The rules of knee injury prevention are simple - avoid off axis strain, avoid torque across the pivot, avoid high sheer forces across the pivot. Off axis strain is an foot/knee/hip alignment issue - I'll get back to that when talking about forces from the foot up. Torque is the twisting force from having your foot held in the wrong orientation, most commonly associated with non rotational cleats. Rotation in pedals is a double edged sword, it makes up for foot rotation due to an offset pivot in either the hip, knee or ankle. It also makes up for the rider moving around on the saddle (CycleBindind made a 100% rigid cleat system that people kept popping out of...). But the knee is a dynamic system, the forces of peddaling the bike can rotate the knee beyond it's own range, so for instance, the knee can see rotation under the force of kicking forward over the top of the pedal stroke and that rotation can be outside of it's range as the pedal moves to the bottom. Cleat fitting would be so easy if cyclists would just stop moving their feet!!!

At this point most people are scratching their heads or clutching their knees, so I'll switch to looking at the forces from the pedal up. The ankle is another one of those screwed up pivots (who designed these things???). Most people pronate (roll inward), so companies like Specialized tilt the shoe slightly to make up for it. It's a sweeping generalization that the whole population pronates, but they add varus to all of their shoes (valgus would be a wedge to roll the foot ourward). In doing a fitting and looking at hip/knee/foot alignment I put a laser line on the rider from the front which shows me center of hip rotation, center of foot rotation and knee tracking. I'll have the rider pedal an easy gear and watch the tracking of the knee, then have them shift into a much harder gear and continue to pedal. If the arch colapses or the ankle tracks inboard, the knee moves with it and I watch their knee move off the laser line. It's common to see a little of that, even with customers who wear custom orthotics while riding - the ankle isn't a zero tolorance pivot. Seeing a lot of shift means the problem must be corrected BEFORE the angle of the cleat can be set or the rotation limited. Think about what's going on there, the ankle is rotating, there is a clear lower and upper side, and there's downward force - the foot will always rotate in that direction. Correcting (or supporting) the pronation/supination problem changes the need for rotation.

A quick word about orthotics. Cycling orthotics are pinned under the ball of the foot and designed to stabalize the arch under force transfer. Many running or walking orthotics are pinned at the heel as heel strike sets up the dynamic for the rest of the stride and full support of the arch removes some of the suspension that the foot offers.

So I guess we're back to the question of which pedal is best. The one that works best with your knees, hips and ankles!!! I've sold a lot of SpeedPlay pedals in both X and Zero models, for people with leg length discrepencies and shims or different length crank arms they seem to work very well. I tend to sell Look CX-6 or CX-7 pedals when I can't get lateral alignment down with any other pedal system. The new Shimano pedals have both float and rotation as well as a nice large platform which stabalizes the foot, so adding shims for alignment makes a very positive difference. I tell my customers to come into the cleat fitting with an open mind...

tbushnel
06-13-2005, 11:52 PM
I appreciate all of the input. knock on wood, things are good now so I'll keep riding the Look pedals. Maybe I'll give the Speedplay zeros a try when the time comes. I currently use custom orthotics but they were made for walking, so I am convinced that a cycling specific pair would be worth it (and maybe covered by insurance... ;) ). Finally, I've been reminded to keep stretching. I have a tendency to let that part of my training program slack a bit.
Again, thanks to all.
Ted.

:banana: :banana: