vivi f26f Manual De Instrucciones página 11

11.2 When you shift forward the right derailleur handle, the back derailleur will
move inside, at the same time, move the chain from the small part of the rear
flywheel to the large part. These steps will reduce the riding speed while riding,
also will reduce the pedaling strength of riding. When the handle bar at the
maximum position(as shown in picture 3 below), press the accelerator button
on the right derailleur handle, the back derailleur will move outward, at the
same time, move the chain from the large part of the rear flywheel to the small
part. These steps will increase the riding speed while riding, also will increase
the pedaling strength of riding.So as to realize the different speed of the back
derailleur.
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