Intro to Bike Gears

Triathletes new to cycling often wonder about two things: how fast should I pedal and, with so many choices, what gear should I ride in?

Deciding how fast you should pedal is the easier of the two questions. The speed you turn the pedals is called cadence. You measure cadence by counting how many times your right (or left) leg completes a full revolution in one minute. Exercise bikes and some spin bikes may display this number for you.

More: Cycling Cadence in Training and Racing

Unless you have a bike computer on your bike you may have to count it yourself. Do this in a safe area where traffic and other hazards are at a minimum. Using a watch that displays seconds, count each time your leg comes up on the pedal stroke for 30 seconds. Now multiply this number by two to get your cadence.

Under most conditions it's usually most efficient to pedal at around 90 revolutions per minute (rpm). Is 65 okay? I would say that's a bit too slow. When you turn the pedals at such a slow cadence you fatigue pretty quickly. What about 75 per minute? You're getting closer and that would be much better.

But once you get into the low to mid 80 rpm range you're pretty close to the sweet spot. Pedaling at this cadence for long periods of time takes practice, so be patient and keep at it.

What if it's just too hard to pedal that fast?

More: Tips to Boost Your Cycling Pace

If it's too hard to pedal at 80, 85 or 90 rpms then you're probably using a bike gear that's too high. Shift into a lower gear to make it easier for you to turn the pedals faster. For new cyclists, it seems complicated because of all of those gears/sprockets/metal-toothed thingys on your bike.

So here's a breakdown:

• Those big, metal-toothed sprockets next to your right pedal are called "chainrings". Most road bikes have two of these but some have one (those are called singlespeeds) or as many as three (better for beginners).  
• The group of sprockets on the back wheel is called a "cassette".
• Each individual ring in the cassette is called a "cog".

More: A Breakdown of Bike Gears

You have two shifters on your handlebars to change these gears. The left shifter changes the chainring gears next to your pedal. The right shifter changes which cog you are using in the rear. The chainrings make the biggest change in difficulty when you change these gears.

In other words, if you move the left shifter you make a big jump, making pedaling either much easier or much harder. If you move the right shifter you make smaller jumps up or down; the right shifter allows for more of a fine-tuning adjustment.

More: Bike Shifting 101

But which one should you use? Use the one that allows you to pedal comfortably in that 80 to 90 rpm cadence range. Start off easier, in the small chainring (the one by your pedal) and one of the middle cogs near your back wheel. Shift (with your right shifter) to a harder cog if that's too easy. If you keep moving the right shifter and it's still too easy, shift to the big chainring. What "number" gear you're in doesn't matter. What matters is being able to turn your pedals at a good cadence while still being relatively comfortable. 

Here are a couple of scenarios: If you are riding up a fairly steep hill you'll probably ride in the small chainring and one of the easiest cogs. If you are on a slight downhill you probably will be in the big chainring and one of the harder cogs. Experiment to see what works for you.

More: Sitting Vs. Standing When Cycling Uphill

Shifting

Finally, shifting gears smoothly takes practice and anticipation. You can't shift bike gears unless you're pedaling. If you're coasting along, not moving the pedals, and you move the shifter, nothing will happen. You must be pedaling forward before the gear will change.

But there's a little trick with this. In order for the bike to shift smoothly you need to be pedaling softly as you change gears. If you're pushing down hard on your pedals as you shift, the gears will probably make a horrible griding sound and may not actually change. Ease up on your force for a brief second or two (don't stop pedaling though) and it will do what you want it to do. 

More: 3 Shifting Tips for Rookie Cyclists

Anticipating Gear Changes

When approaching a hill, you should shift into the small chainring slightly ahead of time, before you start to slow down too much. As you go up the hill, if that isn't easy enough, you can shift to an easier cog. Try to anticipate this so you can shift before it gets too difficult. Once the hill begins to flatten out or you reach the top, you will shift to a harder cog and, if need be, to the big chainring. You want to anticipate this as well, so that your legs aren't spinning around without purpose.

Practice! Prop your bike's rear wheel up off the ground, or ask someone to hold it up for you. Turn the pedals with your hand and move the shifters so that you can actually watch as the bike gears change. Then take your bike to a parking lot or a hard grass or dirt field and practice gear changes. This way you won't have to worry about cars, obstacles or other riders while getting used to your gears. You will gain confidence and be more comfortable after a little practice.

More: A Breakdown of the Cycling Pedal Stroke