I opined:
>If you're bound and determined to use (yuck!) half-step-plus-granny,
>basically any "double" type front derailer will work fine.
...and only later recalled an article I wrote a year ago but forgot to link to the rest of my site:
http://sheldonbrown.com/
Joseph Bender-Zanoni top-posted:
>I don't understand the attacks on the half step plus granny. Yes,
>modern equipment has rendered it obsolete. But for classic bikes,
>what is the proposal?
For classic touring bikes, that's perfectly reasonable. Converting a
racing-type bike this way, however, is simultaneously "inauthentic"
and sub-optimal.
>Yes, you need to shift a lot. And the gear charts on the stem are nerdy.
You say that as if it was a _bad_ thing! All of my bikes have such
gear charts, but I do mine with Photoshop and color coordinate them
to the bike they're taped to. ;-)
>But you can dial in a really great set of ratios using classic era
>components and building custom freewheels. With no overlapping
>gears. Plus you can set up a super low granny at no detriment to all
>the closely spaced ratios in your power range. In my touring
>experience, you can't have enough ratios spaced closely (say every 3
>gear inches) and evenly around 65-70 gear inches and it is a good
>idea to have a gear as low as 20 gear inches. What people forget to
>consider is that tendonitus and other physical problems can flair up
>on a long tour and you can either stop and rest, abandon or take it
>extremely easy.
I have nothing against the "granny" part, it's the "half-step" part that I dislike.
I must admit that much depends on the terrain. I learned this a few years back when a visiting rider from California was rhapsodizing about how nice the riding was in my area (rolling New England terrain.)
She said: "When you do a century in California, it's 2,000 feet up, 2,000 feet down, and 85 miles of flats."
For that sort of riding, I can see that HS+G makes some sense. You have the granny for the climbing, then a set of very tightly spaced flatland cruising gears, letting you fine tune the gear you will be in for the 85 miles.
For rolling terrain, however, where you're shifting all of the time (and when I could ride, I would usually shift at least a dozen times per mile, when riding a bike with gears) the need for constant double-shifting makes HS+G a major hemorrhoid.
Local riders who have read and followed recommendations of HS+G commonly wind up not using the prescribed shift sequence with every other shift a double shift, so in effect they wind up with bigger jumps, using the rear derailer for most shifting, as most cyclists do.
Sheldon "Wide In Front, Narrow In Back" Brown
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| A: Because it disrupts the natural flow of conversation. |
| Q: Why is top-posting frowned-upon? |
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