Currier Tech Ezip, Owner'S Manual, Page: 114 / 123

114
? shifting
Your multi-speed bicycle will have a derailleur drivetrain, an internal gear hub drivetrain or, in some special cases, a
combination of the two.
1. Why all those gears?
You will get the greatest fitness benefit, produce the greatest sustained power and have the greatest endurance if you learn to
spin the pedals at high revolutions per minute (called cadence) against low resistance. You will get the least fitness benefit and
have the least endurance by pushing hard on the pedals against heavy resistance.
The purpose of having multiple gears on a bicycle is to let you chose the gear that allows you to maintain your optimum
cadence under the widest range of riding conditions. Depending on your fitness level and experience (the more fit, the higher
the cadence), optimum cadence is between 60 and 90 pedal revolutions per minute.
2. shifting a derailleur drivetrain
If your bicycle has a derailleur drivetrain, the gear-changing mechanism will consist of:
• A rear sprocket cluster, called a freewheel or freewheel cassette
• A rear derailleur
• Usually a front derailleur
• One or two shifters
• One or two control cables
• One, two or three front sprockets called chainrings
• A drive chain
The number of possible gear combinations (“speeds”) is the product of multiplying the number of sprockets at the rear of the
drivetrain by the number of sprockets at the front (6 x 2 = 12, 6 x 3 = 18, 7 x 3 = 21 and so on).
a. Shifting Gears
There are many different types of shifter mechanisms, each preferred for specific types of application because
of its ergonomic, performance and price characteristics. The designers of your bike have selected the shifter
design which they believe will give the best results on your bike.
The vocabulary of shifting can be pretty confusing. A downshift is a shift to a “slower” gear, one which
is easier to pedal. An upshift is a shift to a “faster”, harder to pedal gear. What’s confusing is that what’s