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Discussion Starter · #1 ·
I currently ride a triple chainring, but the granny has been collecting dust for the past three years. I plan to swap it out for either a double or a compact, but I'm on the fence on which way to go. The current setup in the front is 50/39/something. The rear cassette is an 11/28. I have learned to shift the front while I'm midway through my cassette, where the spacing is tighter; only using the last four lower gears for the hills. I'm used to the gearing, and it works well (It's a 9 speed btw).

Going to a double would provide some top end with no change in the low gears. Going compact would allow me to tighten up the gears in the rear. I think I could get down to a 11/25 and still have the same benefits as I do today.

What's your preference? I'm 43, as light as I will ever get, and average 21.5 on our group rides (only 30 miles, but with some hills. Live in Mass). So I am no means a strong rider. I read that people are better off on compacts as they age.

Okay, one other thing. There seem to be more rippin deals on doubles. Compact seem more expensive. I am looking at Ultegra level if I were to change.

Thanks

Pete
 

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Here's my thinking.

A 50-11 gear is between a 53-11 and a 53-12. So unless you need a 53-11 to keep up with your buddies, it doesn't seem to be a very big deal to go to a 50-11 top end gear.

Where I live, a 11-23 cassette works great! Very close gear spacing with essentially no crossover gearing.

Going to a hilly area, all I have to do it swap to a 11-28 and I have climbing gears. FYI - I do size my chain for the 11-28, and it still works fine with the 11-23.

The question you have to answer is - does a 34-28 gear work for my steepest climb. If not, you are either back to a triple or 11-34 cassette and a long cage derailleur. But that second option is a whole different topic.
 

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Don't approach it like that: double vs. compact. Do the math. First, figure out the extremes you need. You don't use the granny, you say, but do you use the 39x28? do you need it? Do you need even lower occasionally? Do you use the 11x50? Do you need it? You note that with a standard double (52) you could get more top end, but do you need that?

When you figure out what high and low you need, chart out the cassette combinations that would get you those with the various chainring combinations. Then see which of those gives you the best spacing in the parts of the cassette where you cruise most often.

My guess is you won't find a huge difference between the crank choices, and you can get what you need with either. But one may have a shift pattern that's more to your liking.

FWIW, I live in central Connecticut, and probably ride in terrain similar to yours. Lots of hills, but few real "mountains" (rare to climb for longer than 2-3 miles). Some very steep short pitches. I get away with 39-52 rings and a 13-26 9-speed cassette. I like to go fast on descents, and my 52x13 top gear (12% lower than your 50x11) is plenty to let me spin up to 35 mph before I tuck in and coast. I'm 60, and I ain't gettin' any stronger, either, or any lighter (but don't seem to be getting heavier, either ;-)

Anyway, there's no substitute for the math, IME. Make up charts of all the possibilities, and stare at them and think about them for a while.
 

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Discussion Starter · #4 · (Edited)
Thanks. You are correct, I don't feel like I have ever run out of gears on the high end. I also have not required anything more than the 39-28 on hills. If I were to go lower on my gearing then I don't think I would ever keep pace with the group.

JCavilia, good points. I just found the calculator and started playing around with it a bit. I am starting to lean towards the compact because the 50-11 seems to be working 99% of the time. Once I'm in the low thirties, I tuck. Additionally, the gearing in the rear, especially if I keep the existing cassette as a backup, provides a ton of range.

Pete
 

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peterk said:
I currently ride a triple chainring, but the granny has been collecting dust for the past three years. I plan to swap it out for either a double or a compact, but I'm on the fence on which way to go. The current setup in the front is 50/39/something. The rear cassette is an 11/28. I have learned to shift the front while I'm midway through my cassette, where the spacing is tighter; only using the last four lower gears for the hills. I'm used to the gearing, and it works well (It's a 9 speed btw).

Going to a double would provide some top end with no change in the low gears. Going compact would allow me to tighten up the gears in the rear. I think I could get down to a 11/25 and still have the same benefits as I do today.

What's your preference?
Keep the triple but switch to a 12-21 or 13-23. 30x21 is the gear you get with 39x28 but the cogs run 12-13-14-15-16-17-18-19-21 or 13-14-15-16-17-18-19-21-23 not 11-12-13-14-16-18-21-24-28 with the gaps in your nice big-ring cruising range.

You could run a compact like 50-34 x 12-23/13-23 although there can be terrain/fatigue combinations where you'll be doing more front shifting due to the limited overlap.

You could also start your cassette with an 11 cog, although you don't need it unless you'll be doing time trials with a serious tail-wind. Down-hill it's faster to tuck. If you can sprint at over 1000W it's not going to hurt you to up your cadence to 120 RPM which will net 36 MPH with a 50x13.

The new cassette will cost a lot less than a new crank set.

I really loved my 50-40-30 x 13-14-15-16-17-18-19-21 8 speed. I moved to 13-14-15-16-17-18-19-21-23 9 speed when Campagnolo discontinued my preferred cassette; and after I wore out the big ring figured I could loose the third ring and get the same low I used to have with 50-34 x 13-23. That usually works great although there are odd wind/terrain/fatigue combinations that lead to a lot of shifting because without getting completely cross chained the 34 ring is only pleasant up to about 17 MPH while the 50 is only nice down to 14 MPH. A 39 or 40 works past 20 MPH and running out of smaller cogs leads to a 2-3 cog shift moving to the big ring (one motion on Campagnolo) versus 5 cogs bigger on the compact.
 
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