Webcor/Alto Velo - Rodamaker Fitting

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   For Alto Velo members, a bike fitting session costs $50. I have done these for a number of years and have all the proper equipment. It takes about an hour. This is about one half to one fourth the cost from an equivalent bike fitting expert who is actually trying to make a living doing this. You might ask what are the advantages of getting fitted. Some of you are probably so close to optimum that the changes are small. You gain some peace of mind but not much performance. Very few of you are likely in this category. For the rest of you, a bike fit goes a long way toward making you one with the bike. Improvements can occur in comfort, stability, aerodynamics and power output. I probably can't improve all of them as there are compromises. When you are pedaling a bike properly, power is produced all the way around the pedal stroke. Having your bike fit really well does not guarantee you will have a beautifully round pedaling motion but it does make it possible.

     Here is how a session goes. I have a two page form where I write down comments about your current setup and document the changes made. First step is to mark the location of your inner metatarsal on your shoes and also put a mark 1 cm behind it. Then you get on your bike on an accurately leveled trainer in cycling clothes and shoes and pedal for a while to be sure you are on your seat exactly as you would be when riding on the road. Pedals are stopped in a horizontal position and a plumb bob is dropped passing through the pedal axle. We want the pedal axle to be 0.5 to 1.0 cm behind the ball of your foot which is the same location as the metatarsal. Cleats are moved to get within the range. There is no such thing as a perfect bike setup however a bad bike setup is easily achieved. If we set the cleats at .5 cm back, we are optimizing spin and pedaling smoothness. Sprinters often like this but you do lose some ability to push hard on the pedals. If we go to 1 cm back, that position is for really optimum force with a slight loss in smoothness. Outside of this fairly small range, you will either lose a lot of pedaling force or be pedaling squares even at moderate cadences.

   Once the cleats are set, we position the seat relative to the bottom bracket. We measure the knee angle at maximum extension and the knee position relative to the pedal axel with pedals horizontal and this is done for both legs. The nominal knee angle is 150 degrees but it can be 5 degrees more or less depending on rider preference. Most riders are too high which creates some problems. Angle excursions of the knee and hip are increased which is not necessarily bad as it does give you a feeling of strength but the knee extension occurs near the bottom of the stroke. You will feel this and use your quads to make it happen but this is the wrong place in the stroke to use your quads. There is a significant aerobic penalty to having your seat too high. If the seat is so high that you have to reach with your toes and rock your hips, you are very likely to have knee problems. The hip rocking puts a bending load on your knee that is really bad. Being a little low is aerobically better than a little too high but you knees will be coming up too high restricting your breathing and the knee and hip angle excursions are reduced so you don't have good pedaling leverage. You can spin but you can't push really hard on the pedals.

   The other aspect of seat position is fore and aft. Nominally it is set by having the knee right over the pedal axle with pedals horizontal. Climbers often like to be 1 to 2 cm behind the pedal as this allows them to use their glutes a little more. They will have to raise their bars a little to avoid restricting their breathing which make them less aero and spinning will be reduced a little but this is the price you pay to be a better climber. If spinning and aero are important, the seat is pushed forward 1 to 2 cm.

    Now, the cleats are set and the seat is positioned relative to the bottom bracket. The final step is to position the bars. This is the least scientific part of bike fitting. In general, low is the same as long. High is the same as short. High and short will be more comfortable but less aero and there are numerous possible hand positions. I try to make it comfortable with hands on the levers. Then you can go lower for powering on the flats by going into the drops or higher by grabbing the bars in the middle. If you never go into the drops, the bars can come up or back. Getting this really right often requires some experimentation on the road. Once the position is accurately set, you can transfer it to other bikes by measurements but this only works if both bikes have the same seats.

To arrange a fitting session, contact Mark at markATmcrfeaDOT.com