What gears are for
Gears let you keep pedalling at a comfortable speed while the bike moves faster or slower, or while the road tilts up or down. They do not make you stronger. They change how far the bike travels for each turn of the pedals and how hard each turn feels.
Most gearing questions come down to one goal: keep your legs turning at a rhythm that feels easy and steady, and change gear when the road changes. If you are working out why one gear feels light and another heavy, the explanation of how bike gears work goes into the mechanics. This guide is about using them.
Easy gears and hard gears
Every gear is a pairing of a front chainring and a rear sprocket. The useful rule of thumb is the same on almost every bike with a derailleur:
- A gear that feels easy to push is for starting, climbing and headwinds. The pedals turn quickly and the bike moves a short way for each turn.
- A gear that feels hard to push is for fast flat riding and descents. The pedals turn more slowly and the bike moves further for each turn.
On the rear cassette, the largest sprocket is generally the easiest gear and the smallest the hardest. On the front, the smaller chainring is easier. Shifters are often labelled with numbers, but the numbers differ between bikes, so learn how your own bike behaves by feel rather than by memorising a chart. The idea behind this, gear ratios, is simply how many times the rear wheel turns for one turn of the pedals.
What the two shifters do
On a typical multi-gear bike the left shifter moves the chain between the front chainrings and the right shifter moves it across the rear sprockets. Many bikes have two or three front rings and a larger set of rear sprockets.
Most of your everyday shifting happens on the right. The front shift is a bigger change, so think of it as the step you take when the rear gears run out of range. Some bikes, including many with a hub gear or a single front ring, have just one shifter. Your bike’s manual or a bike shop can explain the controls on your particular model.
Shift early, shift lightly
Two habits make gears quieter and more pleasant to use.
First, change gear before you need to. If a hill is coming, an easier gear chosen beforehand is much smoother than one forced halfway up. The same goes for stopping: drop into an easier gear while still rolling so you can pull away comfortably.
Second, ease the pressure on the pedals for a moment as you shift, while keeping them turning. Shifting while pedalling hard puts strain on the chain and can cause crunching noises. Chains need movement to change gear, so never shift while the pedals are stationary on a derailleur bike, but do soften your push.
Finding a comfortable rhythm
A steady rhythm usually feels better than slow, heavy pushing. This rhythm is called pedalling cadence, and most riders find it more sustainable to spin a lighter gear than to grind a heavy one. There is no single correct number. A rhythm that feels smooth and lets you breathe easily is a good starting point, and it will vary with your fitness, your bike and the terrain.
A useful test: if your knees feel strained or you are bouncing in the saddle, you are probably at one extreme. Shift so the pedals feel lightly loaded but not spinning freely.
Matching gears to the road
- Flat roads: pick a gear where you can hold a comfortable rhythm without effort building up. Shift harder as speed rises and easier as it falls.
- Climbs: change to an easier gear in advance, as the road starts to rise. Good climbing gears are usually the ones you can keep turning steadily without standing up straight away.
- Descents: you may run out of gears at the hard end. It is fine to stop pedalling and coast. Keep your hands ready on the brakes.
- Rolling terrain: short ups and downs reward small, quick shifts so you keep momentum; the specifics are in the piece on using gears on rolling terrain.
- Stops and junctions: shift down as you slow, so the bike is in a sensible gear when you start again. This matters more than most beginners expect and is part of starting from a stop on a bike.
Gears to avoid combining
Some front and rear combinations leave the chain at a steep angle. Running the big front ring with the biggest rear sprocket, or the small ring with the smallest sprocket, is called cross-chaining. It can add noise and wear, and there is usually a neighbouring gear that gives almost the same feel. If you notice rubbing, move to a different pairing.
Common problems
If the chain jumps, rattles or shifts late, the cause is often adjustment or wear rather than your technique. Look at what causes skipping gears for the usual suspects. Do not poke at a moving chain or derailleur with your hands or feet. Adjustments and repairs are best done by a bike shop or following the manufacturer’s instructions.
A quick chain and gear check before a ride can catch trouble early, such as a dry chain or a stiff cable.
Practice
Find a flat, quiet, traffic-free place such as an empty car park or a quiet path. Wear a helmet. Ride along at an easy pace and shift one step at a time, listening and feeling for the moment each shift lands. Try starting from standing in different gears to feel why an easier gear is kinder on the legs. Little by little, the choices become automatic, and you can spend your attention on the road instead of the shifters.
Outcomes vary between bikes and riders, and none of this replaces advice from a bike shop about your specific setup.