How to use Bicycle Gears
Bicycles have multiple gears so
that it's easier to go up hills, and so you can go faster on
level ground. Read this article and in five minutes
you'll know how to use your gears.
First, let's get our terms straight so we're on the
same page
You can think of gears as the same thing as
speeds  a bike with 18 gears is an 18speed
bike. Bikes generally have 1, 3, 18, 21, 24, or 27
speeds. (10 and 15speeds are obsolete and you don't see
them on new bikes any more.)
Lower numbers are the low gears, and higher numbers
are the high gears. First gear is a low gear.
Twentyfirst gear is a high gear. That's pretty easy,
right?
Shifting means going from one gear to another.
You shift gears by sliding the shifter on the
handlebars. On most bikes this shifts the chain onto a
different sized ring. On threespeed bikes the gears are
inside the hub of the wheel so you don't see them.
Downshifting means going to a lower gear, and
upshifting means going to a higher gear. You can
also say shift down and shift up.
How do I tell what numbers my gears are?
If your bike has three speeds then telling the
gears apart is easy, because there's only one shifter and
it's labeled 123. You can skip the rest of this section
and go on to the next one.
But if your bike has 10 or more speeds then it's just
a little bit trickier, because you have two shifters.
Let's say you have an 18speed bike. Your left shifter
will be labeled 123, and your right shifter will be
labeled 123456. This means that for each number on
the left, you get six different speeds on the right, for
a total of 18. Here's how it works:
Left shifter #1

Left Shifter #2

Left Shifter #3

1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


Shifting moves the chain onto a different ring.
Moving the lever changes where the chain is.

The Rear Ring
12346789
´´ Lower  Higher
ªª
Your bike might
have only 6, 7, or 8 rings.

The left shifter changes the ring next to the
pedals. The smallest ring is 1, the middle ring is 2,
and the biggest ring is 3. When you downshift with your
left shifter, you're moving to a smaller ring.
The right shifter changes the ring on the rear
wheel. This is opposite of the front set: On the rear
wheel the biggest ring is 1, and the smallest ring
is 6.
You don't have to worry about the ring sizes if you
don't want to, you can just look at the numbers on the
shifter. You can downshift with either shifter,
moving it from a higher number to a smaller number. You
get a bigger change when you shift with the lefthand
shifter than when you shift with the righthand
shifter.
Now that you know what the terms mean, let's see how
to use our gears
Here's pretty much all you need to know about
shifting gears:
 If you're going uphill and it's too difficult,
shift down.
 If your legs are spinning the pedals way too fast
(it's too "easy") then shift up.
That's it, in a nutshell. Of course there are nuances
but that's 90% of what you need to know.
Here it is with more detail:
Let's say you're on a threespeed bike, in second
speed. You start to go up a hill, and suddenly your legs
can't spin the pedals as fast. You're barely turning the
pedals, pushing hard on them, and you're going so slowly
you think you might fall over. The solution? Downshift to
first gear.
How does that solve the problem? First gear moves you
a shorter distance for each spin of the pedals, which
makes it easier to pedal.
Now let's say you've reached the top of the hill, and
you start going downhill slightly. Soon you find there's
no resistance in the pedals  you can spin them as fast
as you want and you're not really getting anywhere.
Solution? Upshift back to 2, and if it's still too easy,
then upshift to 3.
This works because the higher gears move you farther
for each spin of the pedals, making you do more "work",
and making it less "easy".
Which shifter to use?
So you've learned the basics: Uphill = shift
down, Downhill = shift up. But you have an 18speed
bike and you're wondering which shifter to use,
the left one or the right one?
It's easy: If
you need a big change, use your left shifter. If you
need a small change, use the right one. As you ride
you'll get a feel for whether you need a big change or a
small change.
Don't bend the chain too much
Try to keep the chain in a sortof
straight line between the front and rear sets, rather
than going at an extreme angle from left to right. For example,
in the very lowest gear the chain will be all the way on
the left on both sets. In the very highest gear the chain
will be all the way on the right. That's fine. What you don't
want to do is to use the leftmost ring in the front and
the rightmost ring in the back, making the chain go
diagonally. That stretches the chain and wears it out. Likewise, don't use the rightmost ring in the
front and the leftmost ring in the back.
Let's say you're in the easiest gear (lefthand on both
rings) and you need to upshift, so you move the chain on the rear set to the middle. That's not
enough for you and you want to upshift some more. At this point, don't
keep shifting the rear set, since that would make the chain diagonal
between the front and rear sets. Instead, shift the front set
from the left to the middle (1 to 2). That keeps your chain nice and
straight.
Let's have another look at our gearing chart. The
green boxes are the combinations you'll use, and the gray
ones are the combos you'll avoid.
#1

#2

#3

1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


1

2

3

4

5

6

RightHand Shifter
(Rear Ring Set)


So yes, you won't use every gear available to you.
You're not supposed to. Which brings us to...
How many gears do I need? Are more gears better?
The everincreasing number of gears on bikes is mostly marketing hype.
For the most part, all the extra gears are useless. My childhood
bike had just 10 gears. Then bikes went to 15 gears. Then
18. Then 21. Now we're at 27. Do you really need that
many gears? No. What you really need is a good range
of gears. You need gears that are low enough for going up tough
hills, and gears that are high enough that you can keep pedaling when
going down gentle inclines. If your gear range is good, the
number of gears is irrelevant.
You can't know the gear range of a bike by the number of gears it has.
It's true that a bike with more gears often has a wider range than one
with fewer gears, but not always, and even if it does, you don't
necessarily need the widest gearrange possible. You just need enough
of a range. (Think of it like this: There's no use in
buying a car that goes 250 mph, because you're not allowed to drive
that fast. More isn't necessarily better.) The only way to
tell what the gear range of a bike is like is to take it on a test
ride, going up the hardest hill you'll be going up in the future, and
going as fast as you care to down a gentle incline.
In fact, if your area is relatively flat, you might not need gears at all.
Or you might be able to get by with as little as three. As I
write this, I'm in Osaka, Japan, where most bikes, including mine, have
just three gears. The low gear isn't as low as I'd like for
getting up hills, but it's good enough. If I were staying here
longer, I'd get a bike shop to make the lower gear lower.
Yes, you can do that. If you've already got a bike and
you're not happy with the gear range, you don't have to get a whole new
bike. A bike shop can change either the front or rear rings
(usually the front) to give you a higher range.
I hope this helps, and have fun with your
gearing!
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