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On The Hunt For Better Gearing...
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So I've been messing with Excel trying to do the math to figure out better gearing. I live in what can be a very hilly area. I am looking for a better balance of gearing, especially at the low (BIG GEAR) end for descending. I can't ever make up any speed on big downhills, since I can't push the watts I want while spinning 120+ rpms.

I currently use either an 12/23 or 12/27 (10spd) casettes depending on terrain. Race cadence (1/2IM) averages 95-100. Usually I'll sit in that 95-105 range.

I've considered the 11/23 or 11/21 option, but I know that Kraig Willet did some drivetrain analysis that says that gears smaller than 14t tend to significantly increase drivetrain friction, and it also seems that 11/23 gives up the 16 which I really like, and 11/21 is not going to be great for going uphill.

So I'm wondering, is a 55/42 a better option for me (still paired to my 12/23 or 27) than a 11/21 or 11/23? Seems the 55/42 with those cassettes gives a better range than using the 11/21 or 23 with my 53/39.

And before anyone suggests it, I do NOT want a compact. I had one. I did not like it.

I have the watts to move a 55/42, but I feel like I ride pretty high cadences, and that might seem to go against conventional wisdom for this set-up.

Price for a 55/42 pair is basically the same as a 11/21 (or 11/23) cassette, so that is not a deciding factor.

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Re: On The Hunt For Better Gearing... [Rappstar] [ In reply to ]
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If you go with that 55 up front, what does that do to wanting the 16?

And as for increasing drivetrain friction... You're already descending and spun out, what does it matter that there's more friction if you can get more speed?

You might consider going with a 54 up front and an 11 in back. Maybe just swap out an 11 (and the compact lockring) for the 12 without changing all the other cogs.

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Re: On The Hunt For Better Gearing... [Rappstar] [ In reply to ]
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I only run a 13t and feel like it's enough. You must be far more powerful, or at least more daring, than I. Spinning out in the high 30's never really seemed like a bad thing before.
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Re: On The Hunt For Better Gearing... [caleb] [ In reply to ]
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Re: On The Hunt For Better Gearing... [Rappstar] [ In reply to ]
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What do you consider a big downhill? At 40+mph they tend to be gone pretty quick.

I think your best bet is to practice spinning at higher rpm's. My biggest gear is a 52x12 and I don't feel spun out until I'm a hair over 45mph on most days. At that speed it's fun to pedal, but it's not real productive. A 55 gives you less than a 4% decrease in RPM over a 53, so 130 rpm might turn into about 125...big whoop, you probably couldn't even tell. Just play with the cassette and see how you like it. I'd go 11/23. If you are worried about drivetrain inefficiencies due to small cogs, just imagine the inefficiency of pedaling beyond 40mph.

If you really want to go big, go BIG. I had a 58-44-30 on for a while, which obviously isn't a typical triple, but with an 11/23 on the back I had all the gearing you could ever need. The perfect mountain triple...kind of wonder why I unloaded it to tell you the truth. Too much peer pressure to get a double maybe?
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Re: On The Hunt For Better Gearing... [Rappstar] [ In reply to ]
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I run a 55/42 and 11-23 on the TT bike, 53/39 and 12-25 on my road bikes

A 55 and 11 is hard to spin!
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