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Old February 18th 18, 02:22 PM posted to rec.bicycles.tech
Duane[_4_]
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Posts: 1,546
Default my fixie doesn't need improvement

wrote:
Op zaterdag 17 februari 2018 23:47:07 UTC+1 schreef jbeattie:
On Saturday, February 17, 2018 at 1:05:08 PM UTC-8, wrote:
On Saturday, February 17, 2018 at 8:57:49 PM UTC+1, Joerg wrote:
On 2018-02-17 01:28, wrote:
On Friday, February 16, 2018 at 7:32:10 PM UTC+1, Joerg wrote:

[...]


Actually, in some situations ye olde friction shifters are better
than anything that came later. In situations where you must quickly
shift from a very high gear straight to almost the lowest, that can
be achieved in about one second simple by an opposite flick of
thumb and index finger on the downtube levers. Only with friction
shifters. Ok, a Rohloff or a similar hub transmission could also do
that. Can Di2?

Of course.


So give us some numbers here, in seconds. How long does it take to shift
from large-small to small large, in one swoop? Faster than this below?

https://www.youtube.com/watch?v=3SHJ7KoJIys


3-3.5 sec. (11 speed ) under full load and out of the saddle if you
want (it will make some noise) and the FD is trimmed after that. You
can shift front and rear at the same time.

I can shift a lot faster than that with friction shifters. Not with
indexed ones on the handlebar or drifters.

I don't think so. One may have some reasons to prefer friction
shifters but speed of shifting can't be a reason. Strange that Pro
riders don't use friction shifters anymore because they like fast shifting.


And it doesn't matter in the real world, at least not on the road. The
perfect example is the Cat's Hill Criterium in Los Gatos.
https://www.youtube.com/watch?v=GrG12-aG_Xc It has a hard left (or
right, depending on the year) up a 20% climb on Nicholson Ave. Back in
the '70s, when everyone was on friction, the set up before the hill was
everyone shifting up to their last gear -- a 19 or 21 -- a second before
the turn, coasting through turn and then over-spinning until momentum
was lost and then out of the saddle grinding. You hit the top, flop down
into the saddle, bobble for your gears and then drop it one or two cogs.
Nowadays with STI and Di2 that can shift under load, you don't need to
run up the cassette before you hit a hill. You keep your hands on the
bars, shift up as you're hitting the bottom of the hill and keep shift
as momentum wanes and the grade sets in. You can shift out of the
saddle as you go unlike friction shifting.

The same goes with shifting to the small cog. Back in the day, you
would hump up some hill out of the saddle, and assuming the hill had a
short enough crest, you would spin across it and then dump the freewheel
over the other side. These days, you can stay out of the saddle and
shift down for the flat crest and keep shifting over the other side. The
dope with friction is in your rear-view mirror.

The reason you had to shift the whole freewheel is that you couldn't get
to your shifters once the hill went up or down or because you couldn't
shift under load. For those on modern equipment, those concerns are a
thing of the past. Shifting into your spokes is also a thing of the past
for the most part -- or missing a shift.

Like I said, STI changed racing. I raced before and after, and it was
like night and day for someone like me who climbed out of the saddle.
Crank, crank, crank, flop down into the saddle get the next gear, stand
up . . . rinse, lather, repeat. In crits there was no longer that
pack-wide wobble as everyone reached down to shift coming out of a
corner or into a corner. That brings up another point. Crits got faster
(and I got older) with people sprinting and shifting out of corners.

-- Jay Beattie.


That is an accurate description how it went in the old days. For me 30
years ago. I know no serious cyclists these days that do not allow
themselves STI shifters or the like because they can break and keep
riding Fred Flintstone bikes. Only people that are into vintage do.

Lou


+1

--
duane
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