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CYCLING PERFORMANCE TIPS

  Last updated: 12/6/2009

Pedals


Weight

I ran across this comment (paraphrased) on an online biking site. " I just spent $200 on nothing. My bike is pretty tricked out: titanium frame, carbon fork, Dura-Ace group, assorted gewgaws. The only exception is the pedals, clunky old Looks. Last week I'm riding with an ex-Cat 1 who says, you could drop a half-pound by getting some new pedals. After the ride I stop at my local bike shop and order some new, 277-gram Dura-Ace pedals. I've just dropped $200 to make 100 grams disappear from my bike. I guess it would be cheaper to shed a few hundred grams from my body."

Not true. Although this seems logical, some weight makes more of a performance difference than an equal amount elsewhere on the bike/body. And that is in the pedals, crankarms, rims and tires. It has to do with the fact that we are always making small accelerations (and decelerations) as we ride - on the flats and on hills. Not big moves, but small changes in speed. With acceleration, inertia in the drive train and in the mass of the bike needs to be overcome - linear inertia in the total weight, and rotational inertia in the cranks and wheels. Rotational inertia is much more sensitive to a set amount of weight than the linear inertia to acceleration from an increase in your body weight or weight elsewhere on your bike. This is why a friend with new wheels will say - "I rode 70 miles and it felt like 50" - after getting a set of Ksyriums.

So remember, all weight on your bike is not the same. And if you are going to upgrade to decrease the weight of your bike, do the rims and pedals first.

Clipless Pedal Technique

Clipless pedals are generally easier to enter than the old toe-clip-and-strap type - if you take a few minutes to practice before your first ride on the road. You'll really like clipless once you learn the "twist out" style of release and it becomes a reflex. Then you'll be able to get out quickly and cleanly, even in emergencies.You shouldn't have to look down while engaging the pedals. That's time-consuming and potentially dangerous. The remedy? Practice a little before you get into that emergency situation. Here are a couple of ideas:

The "Q factor"

This is the measurement between the pedal mounting surfaces (outside surface) on the crankarms (and indirectly the distance between the midline of each foot - which translates all the way up to the knees and hips.) The easiest way to determine Q-factor is to remove one crankarm and mount it in-line (not at the 180 degree rotation you use with riding) with the other, then measure the distance between the outside faces of the arms.

Another aspect is the distance between the crankarm and the pedal platform itself. You need more clearance there if your ankle bone hits the crankarm, if you purchase wider shoes or if your winter booties rub the crankarm. You may feel more comfortable with your feet in an outward position (though a few riders prefer the opposite.) The ability to fine-tune Q-factor means that you can make two bikes match, such as your mountain and road bikes. Mountain bikes typically have a significantly wider Q- factor.

Some pricey pedals allow you to adjust the location of the pedal platform and thus the perceived "Q factor", but there are much less costly ways to do so. If you need only a couple of millimeters additional clearance, get a spark-plug washer at an auto-parts store and simply slip it over the pedal axle before you thread it into the crankarm. Depending on the length of the threaded portion, you may be able to use two or three washers for greater spacing. Make sure there's at least half an inch of thread on the pedal shaft in the crankarm.

Is this a big deal for riders? Plenty of serious riders who train and race on road bikes and mountain bikes experience two different Q-factors without problems. So I'd adjust for what feels right for you.


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Cycling Performance Tips
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