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EXTRAS

Training tips

Never changed gears on my bicycle, and I do just fine, thank you. This is a stock phrase uttered by those who don’t really understand bike gears. If you own a multi-speed bicycle, but ride it like a one-speed, listen up. Learn how to use your bike and your body to their fullest.

Today's bicycles can have up to 27 "speeds" or gears. So what?

If you have ever driven a car with a manual transmission, you know the engine works most efficiently when you keep it working within a certain range of revolutions per minute (rpm). Shifting gears keeps the engine within the range.

Bicycles follow the same principle. Except, on a bike, your body is the engine, and how fast you are pedaling determines the rpm.

From 70 to 90 pedal rpm is ideal for bicycling. It should be maintained uphill, downhill, on flatland, against a head wind or with a tail wind. Pedal rpm translates into cadence, and the goal is to keep this constant. As terrain changes, shift gears to maintain cadence, not speed: Use easier gears to climb hills; harder gears to descend them; and medium gears to cross flatland.

Everyone has a different cadence. This is obvious when you observe people walking, running or pedaling in a group. People move their bodies at different rates over varying distances.

Keeping your bike in high gear ­ one with more resistance ­ does not necessarily make you go faster. Instead, it can stress out your legs. And using all legs to go faster doesn’t work because bicycling is essentially an aerobic activity. Strong heart and lungs are the key. Therefore, to increase speed, work up to a cadence at which you feel steady and comfortable for long periods of time. A higher cadence in any gear equals greater speed.

Many factors play a role in determining which gear to use. We have already explained why desired speed is not a consideration. Now let’s see what is important to gear selection.

The bike’s sprockets (those round sawtooth discs that the chain sits on) are in effect the bike’s transmission. The two or three sprockets in front are connected to the bike’s pedals. From five to nine sprockets abut the real wheel.

Choosing a gear boils down to deciding which two sprockets the chain belongs on at any one time. Maximizing cadence stability is the goal.

As you sit on the bike, look down (but watch out for that parked car ahead!) and notice the chain's position relative to the sprockets.

If the chain is positioned all the way to the left, nearest the bike's frame, on both the front and back sprockets, then you are pedaling the smallest, easiest gear.

If the chain is all the way to the right, as far away from the bike's frame as it can get, on both the front and back sprockets, then you are pedaling the largest, hardest gear.

Other combinations result in the middling gears. Shifting the chain in towards the bike on either the front or the back will give you an easier to pedal gear. Shifting the chain out away from the bike on either the front or the back will give you a harder to pedal gear.

Enough theory. Now hands on: Put your hands on the shifters and play with the gears until you get the feel of them. Don't be afraid to change gears -- you won't break the bike! Start with the chain on the middle sprocket in the front (or the smaller one if you only have two) and experiment shifting the rear gears. Once you have mastered the rear, experiment with shifting the front.

Now are you are ready to switch gears and enjoy riding more?

Jim Guthrie teaches electricians’ apprentices at Milwaukee Area Technical College. Arthur Ross is the pedestrian-bicycle safety coordinator for the city of Madison, Wisconsin.