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Old 11-13-08 | 01:31 AM
  #8  
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Andy_K
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From: Beaverton, OR

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Let me explain what I think the issue is with the 11-32+ cassettes and the wider gear spacing. It isn't something that feels obviously wrong. It's a matter of efficiency.

My maximum efficiency is at a cadence of around 90-100. When I get to about 105, I shift up. If I'm using an 11-32 cassette, that upshift typically drops me down to a cadence of about 80. If I'm using a 12-25 cassette, it typically only drops me to about 90.

Now a cadence of 80 doesn't feel wierd. It's fairly normal. But it's not as efficient as 90, and so I have to work harder to get back into the sweet spot. With the tighter gear spacing, I stay in the sweet spot. The effect is, when my shift takes me to 80, it feels like the bike wants to stay at the current speed, and I have to work to make it do otherwise. When the shift takes me to 90, the bike feels like it wants to go faster.

Obviously in a 'cross race there are all kinds of things that tend to force your cadence down independent of gearing. On the road, the above argument is much more direct. Nevertheless, I think that the net effect of tighter gearing is more efficient acceleration through the range. The cost, of course, is a smaller range.

Mountain bikes use the wider range, because mountain bike riding requires it -- lots of ascents and descents. Road bikes use tighter spacing because the focus is one being able to accelerate efficiently through the range. I would argue that in this respect cyclocross is more like road than mountain.
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