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Shifting Gears

Your multi-speed bicycle will have a derailleur

drive train, an internal gear hub drive train or, in

some special cases, a combination of the two.

How a Derailleur Drive Train Works

If your bicycle has a derailleur drive train, the

gear-changing mechanism will have:

A rear cassette or freewheel sprocket

cluster.

A rear derailleur.

Usually a front derailleur.

One or two shifters.

One, two or three front sprockets called

chain rings.

A drive chain.

Shifting Gears

There are several different types and styles of

shifting controls: levers, twist grips, triggers,

combination shift/brake controls and push

buttons. Ask your dealer to explain the type of

shifting controls that are on your bike, and to

show you how they work.

A downshift is a shift to a "lower" or "slower"

gear, one that is easier to pedal. An upshift is

a shift to a "higher" or "faster", harder to pedal

gear. To select a gear that will make pedaling

easier on a hill, make a downshift in one of two

ways: shift the chain down (the gear "steps" to

a smaller gear at the front) or shift the chain up

(the gear "steps" to a larger gear at the rear.)

So, at the rear gear cluster, what is called a

downshift actually moves the chain up to a

larger gear. The way to keep things straight is

to remember that shifting the chain in towards

the centerline of the bike is for accelerating and

climbing and is called a downshift. Moving the

chain out or away from the centerline of the

bike is for speed and is called an upshift.

Whether upshifting or downshifting, the bicycle

derailleur system design requires that the drive

chain be moving forward and be under at least

some tension. A derailleur will shift only if you

are pedaling forward.

Shifting the Rear Derailleur

The right shifter controls the rear derailleur.

The function of the rear derailleur is to move

the drive chain from one gear sprocket to an-

other. The smaller sprockets on the rear wheel

gear cluster produce higher gear ratios. Pedal-

ing in the higher gears requires greater pedal-

ing effort, but takes you a greater distance with

each revolution of the pedal cranks. The larger

sprockets produce lower gear ratios. Using

them requires less pedaling effort, but takes

you a shorter distance with each pedal crank

revolution. There are two set screws or limit

screws on the rear derailleur body that limit the

travel of the rear derailleur. Tightening the rear

derailleur high gear adjustment screw keeps

the chain from shifting off the small (high) gear

that is on the rear axle. Tightening the rear

derailleur low gear adjustment screw keeps the

chain from shifting off the large (low) gear into

the rear wheel. Moving the chain from a smaller

sprocket of the gear cluster to a larger sprocket

results in a downshift. Moving the chain from

the smaller sprocket on the chain rings to a

larger sprocket results in what is called an

"upshift." In order for the derailleur to move the

chain from one sprocket to another, the rider

must be pedaling forward.

Shifting the Front Derailleur

The front derailleur, which is controlled by the

left shifter, shifts the chain between the larger

and smaller chain rings. Shifting the chain onto

a smaller chain ring makes pedaling easier (a

downshift). Shifting to a larger chain ring makes

pedaling harder (an upshift). There are 2 (two)

adjustment screws on the front derailleur: one

is to limit the travel of the front derailleur so

that the chain can be shifted upwards towards

the larger, higher or harder to pedal gears but

will not allow the chain to "overshift." The other

screw limits the travel of the front derailleur

towards the smaller or easier-to-pedal chain-

wheel. By limiting travel, it prevents the chain

from "undershifting" and keeps the chain from

falling off the chainwheel onto the frame.