In article .com, Jim
wrote:

Hello there,

I was reading the Trek Web site, and found the 520 comes with bar-end
shifters.
What benefits do the Shimano Dura-Ace bar-end shifters offer, compared
with
modern integrated shifters? Is the 520 the only modern bicycle equipped
with
bar-end shifters?

Thanks in advance.

-Jim




Here are a few benefits of bar-end shifters :
a) should they need to be replaced, they're more economical than
brifters[1]
b) Shimano DA/Ultegra rear bar-end shifters offers both index and
friction mode. This is convenient should you bend your rear derailleur
hanger or damage the rear derailleur itself, both circumstances which
can wreak havoc with indexed shifting.
c) I find bar-end shifters are more durable, having a simpler, more
robust mechanism (less parts to break). Not sure if this is
representative of other Shimano brifters, but in heavy rain my (soaked)
Tiagras frequently skip (fail to retract cable) on the down-shift,
while the action of the bar-end shifters' indexed shifting is much more
precise and positive in all conditions.
d) The left bar-end shifter (friction only) allows for very accurate
trimming of the front derailleur.
e) On a more esoteric note, a single sweep of a bar-end shifter can
up-shift multiple gears; Shimanos brifters (my Tiagra/Shimano 600, at
least) can only up-shift one gear at time. I'm uncertain whether this
limitation applies to newer incarnations of Ultegra or DA.

In short, bar-end shifters emphasize durability, versatility (those
with indexed and friction modes) and economy; they're more suited to
the demands of touring or commuting. I'm not sure if the 520 is the
only 'modern'(?) bike equipped with bar-end shifters, but almost any
bike with drop bars is a candidate - and with the addition of Pauls
Thumbies, MTBs too can be so equipped.


Luke


1.
brifter: integrated brake/shifter unit