Quand le
dérailleur
est de rigueur?
-- Brigitte Niquette
 lthough
it may be somewhat difficult to make out in the
photograph on the left,
Brigitte's mountain bike is configured with conventional
gearing as depicted
in the sketch on the right.
 
Look closely and you will see that
the...
-
'Crankset' has
three sprockets, each
one selectable by the 'front dérailleur'
and
the...
-
'Freewheel' has
seven sprockets, each
one selectable by the 'rear dérailleur'.
Look closer still
and you will be able
to count the 'teeth' on each sprocket...
-
Crankset: 28,
38, 48, and...
-
Freewheel:
13, 15, 18, 19, 21,
24, 34
It is customary to
provide an 'index'
for each dérailleur
to denote the present position of the 'chain'...
-
Front dérailleur:
#1~28,
#2~38, #3~48, and...
-
Rear dérailleur:
#1~34,
#2~24, #3~21, #4~19, #5~18, #6~15, #7~13
The puzzle entitiled
"Inches
per What?" provides the rationale for measuring
the 'speed' of a bicycle
in 'inches' along with how to perform the requisite
calculations.
|
How
many 'speeds' are determined
by the dérailleurs on Brigitte's mountain
bike?
|
|
