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Old 02-10-11 | 03:30 AM
  #16  
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Drew Eckhardt
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Joined: Apr 2010
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From: Mountain View, CA USA and Golden, CO USA

Bikes: 97 Litespeed, 50-39-30x13-26 10 cogs, Campagnolo Ultrashift, retroreflective rims on SON28/PowerTap hubs

Originally Posted by travkat
FTW...SRAM Apex and your set!
Sounds great if you're in the bike business (fewer SKUs mean higher profits), if you don't care about performance (a double is easier to adjust and perhaps less confusing to people), or if you have "friends" who'd laugh at a triple but let pie-plate sized cogs pass.

Looks lousy if you're riding a road bike and want to be faster to burn more calories in less time or keep up with a group (racing is a theoretical consideration, although to be competitive you'd have the weight and fitness to run 53-39 x 12-13-14-15-16-17-18-19-21-23 in most terrain and wouldn't be thinking about a such a configuration).

The Apex wide-range gearing is 50-34x11-12-13-15-17-19-21-24-28-32.

The same range in a triple can be had with 53-39-28 x 12-13-14-15-16-17-19-21-23-26.

The later makes it easier to ride just a bit harder without running out of RPMs on the high end when you're already fatigued or keeping your power up by mashing the pedals hard enough that your ride tomorrow sucks.

I can go out, have a nice 45 minute tempo ride in the morning and a hard 45 minutes in the evening averaging 200W pedaling 80-90 RPM, try the same thing tomorrow but struggle to make 180W in the evening, and still be slow after a rest day.

Or I can keep my cadence over 90, ride 3x10 at 205-235W on today's evening ride, average 200W tomorrow evening, take a rest day, and do about as well the next two days. While 100-110 RPM works great for shorter intervals or one 10 minute effort I'm not going to do it for any great length of time.

With the big gaps in gearing either I'm going to push for the power and have weak work-outs the rest of the week or compromise by taking it easy every day.

To do a little bench racing as internet denizens do, at nice cruising speeds the wide range double can call for a 50% power increase to maintain the same cadence in the next gear (aerodynamic drag increases with the square of velocity and distance increases linearly making power required to overcome it proportional to the cube of speed) moving from the 15 to 13 cog.

Allowing cadence to drop from 100 to 90 means the power increase required would be only 12% which looks OK until you consider that blood lactate levels are approximately proportional to power raised to the fourth level, or 57% higher with the big gear jump. Over 10 minutes that's the difference between a little uncomfortable and painful counting down minutes remaining.

It's a straw man but might go farther than saying "I rode a triple with the same high and low as the preceding wide range double for a decade, and it was way better"

Last edited by Drew Eckhardt; 02-10-11 at 04:10 AM.
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