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| English
English |
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Functioning and Operation
Derailleur gears always work according to the following principle:
Large front chainring – heavy gear – bigger gear ratio
Small front chainring – easy gear – smaller gear ratio
Large rear sprocket – easy gear – smaller gear ratio
Small rear sprocket – heavy gear – bigger gear ratio
Normally, the shifters are mounted as follows:
Right-hand shifter – rear sprockets
Left-hand shifter – front chainrings
There are meanwhile various gear systems with one, two or three front chain-
rings.
Modern road racing bicycles can have up to 33 gears. As there are, however,
overlapping ranges, actually 15 to 18 gears are usable.
The chain should not run at an extreme angle, otherwise it wears down and
efficiency decreases. An unfavourable run of the chain is when the smallest chain-
ring is used with one of the two or three outermost (smallest) sprockets or when
the largest chainring is used with one of the inmost (largest) sprockets.
Note:
Avoid gears which
involve an extremely
oblique run of the chain.
Danger:
Practise shifting gears in a place free of traffic until you are familiar with
the functioning of the different levers or twist grips. If you do so in road
traffic, your attention might be drawn off from possible risks.
Danger:
Shifting gears under load, i.e. while pedalling hard, can make the chain
slip. At the front derailleur the chain may even slip off the chainrings when
shifting under load. Furthermore, this can lead to a chain-suck, i.e. the
chain can get jammed between chainstay and chainrings. This can result
in a fall. This will at least shorten the service life of the chain and damage
the frame.
Brake Lever/Shifter Systems
Depending on the gear system, gear shifting is initiated by actuating a brake
lever/shifter unit or by a shifter in the case of flatbars. Continue pedalling during
gear shifting, however, at reduced pedalling force.
The most common brake lever/shifter units and their method of operation are
explained in the following. It is, however, also possible that your new bicycle has a
gear system that is not mentioned.
In the case of
Campagnolo Ergopower
you shift with the shifter located
behind the brake lever to the larger chainrings or sprockets by moving it with the
index or middle finder inwards.
By pressing with the thumb on the shifter inside the unit the chain moves on
the smaller chainrings or sprockets. By pressing the shifter once you can shift up
to two chainrings or three sprockets at a time.
In the case of
Shimano Dual Control
brake lever/shifter units you shift to
the larger chainrings or sprockets by moving the entire brake lever inwards. You
can shift up to two chainrings or three sprockets per gear shift stroke. By moving
inward only the small lever located behind the brake lever the chain moves on
the smaller chainrings or sprockets. You can shift only one chainring/sprocket
per stroke.
The
Di2
is the electronic version of the high-quality drive groups from
Shimano
. Instead of cables the signal is transmitted by wires. The rear and the
front derailleurs are moved by small electric motors. The power supply is provided
by a rechargeable battery that is mounted to the frame.
The shifters are positioned and actuated like the mechanical gears: With a Di2
you must only press control buttons, instead of pressing the entire brake lever or
the lever positioned behind inward as is the case with usual dual control shifters
from Shimano.
Shift to the larger sprockets by pressing the long control button on the side
of the brake lever. Pushing the triangular control button that is located behind the
brake lever makes the chain move to the smaller chainrings/sprockets.
For more information on adjustment and maintenance of the Di2 visit the web-
site www.shimano.com
SRAM Force
brake levers/shifters have only one shifter that is located behind
the brake lever. With one complete sweep of the shifter, the rear derailleur shifts in
a higher gear by one to two chainrings or three sprockets. With a short sweep the
chain changes to the next smaller chainring or sprocket.
