Re: Gain Ratios and CX

On Jul 28, 7:32 pm, John Forrest Tomlinson <usenetrem...@xxxxxxxxxxx>
wrote:
On Mon, 28 Jul 2008 17:31:15 -0700 (PDT), Scott

<hendricks_sc...@xxxxxxxxxxx> wrote:
On Jul 28, 5:16 pm, John Forrest Tomlinson <usenetrem...@xxxxxxxxxxx>
wrote:

The poor shifting on the front end was a common complaint with first
generation compact cranksets.  Advances in chainring pickup ramps and
also in front derailleurs redesigned to work better with compact
cranks has practically eliminated any problems with shifting between
the rings.

I'm not talking about the derailleur.  I'm talking about the legs -
that's a big change in cadence/feel for a single shift.

  Plus, I find that using the 50/34 and a 11x26, I can stay

in the big ring on more occasions.  Many a little bump that might
require a downshift from the 53x23 (big ring, next to biggest cog) are
manageable in a 50x23 gear.  It takes a much more significant climb,
either in steepness or length, to require a downshift from the big
ring when you're using a compact crankset compared to a full-size
rig.  You might be surprised in what you can climb in a 50x23.

I have use 51 x21 a lot so I can imagine.  But I use 51 x42 or
occassionally as small as 38.  I greatly prefer the larger small ring
on course that involve front shifting.

Oh, I assumed you were talking about the shifting issues. OTOH, I
still don't see any real legitimacy to your point. I mean, who does
single shifts of the front ring without also shifting the rear end,
too?

You can do the math, but I'll share with you what I found. If you
shift from the big ring to the small ring without also shifting the
rear end to a smaller cog, you end up with a BIG change whether you're
using a conventional or a compact crankset. The difference is quite a
bit bigger w/ the compact crank. Most people shift the rear end at
least one cog, too, to minimize the drastic change to the legs you
mention.

With the quality of today's shifters, it's no more difficult to shift
the rear derailleur twice or even three times than it is to shift it
once. The differences between the ratios achieved when shifting a
conventional crank vs a compact crank can be minimized by shifting one
extra cog on the rear. For me, this is absolutely not a big deal.
The benefits to having a substantially lower low end, a slightly
higher high end, and less overlapping ratios when using a compact
crank in my opinion significantly outweigh any detriments brought on
by having to shift the rear derailleur an extra cog when shifting from
the large to small ring (or vice versa).
.

Relevant Pages

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