Try an experiment. Borrow a BMX bike and pedal it up and down your street. You’ll probably find it very hard work and, even over a short distance, some leg muscles will complain. That’s because the seat is too low for the powerful muscles in your thighs to work efficiently. Many recreational cyclists are working too hard because their seats are too low.
Getting your seat height right can alleviate pain and help you pedal more efficiently. Even if you’re just cruising the bike path on a Sunday afternoon, you want to get the most power for effort from your body. Think of your heart and lungs as your bike’s motor and your legs as the machinery that transfers power to the wheels. If they can’t stretch out far enough then you’re making life hard for yourself. So, how high should it be?
One guide is 96% of your leg length. Measure your leg length in two sections: from the outward bump on your hip to the middle of your knee, then from your knee to the middle of your ankle. Add these together and multiply by 0.96. Next add an allowance for the soles of the shoes you usually wear. Now you’re ready to transfer the measurement to your bike. Arrange your downward pedal so the crank arm is in line with your seat tube. Measure from the top of your saddle to the top of your pedal. That distance should be the same as the one you just calculated.
There are other guides. With the heel of your foot on the pedal, your leg should be fully extended. Or try setting it up so both toes just skim the ground together when you’re sitting on your seat.
If you need to raise your seat, do you make the change all at once or in small steps? Listen to your body. Try the new height. It will feel odd at first, but you will get used to it. If it causes you pain, though, drop it again and raise it in stages. This gives the leg muscles that have been cramped up time to stretch slowly.
If it all just feels wrong, ask an experienced cyclist for help. They’ll reassure you that getting your seat right is going to help you pedal further without tiring. It all gives you greater control of your bike and makes you a safer cyclist.
See you on the road soon, God willing. Eddie Barkla
First published in the Bendigo Weekly Friday 21 July 2006