Currie tech IZIP - Gear Shifting Explained

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
Yourmulti-speedbicyclewillhaveaderailleurdrivetrain,aninternalgearhubdrivetrainor,insomespecialcases,a
combination of the two.

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.

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