How many decades have engineers been working on "improving bikes" without providing a good shifting system? How many more would ride if pedaling were easier? You would think some big bike customer would be pushing for better engineering. It shouldn't be hard to engineer. It's very easy to spec out. All that is preventing it today is:

1- no 11 tooth chainrings
2- derailers unable to handle 38 tooth spread between High and Low.
There may be other engineering opportunities, but only reason it's not being done is too may are NOT asking for it.

See the specs: High crank ring only, middle crank ring only, low crank ring only and all crank rings:

Look at these numbers and drool



HIGH GEAR
===============
Wheel Diameter: 27.00 inches
Gears: 54 11-12-13-14-15-16-17-18-19-20-21
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
1> 54x21 69.43 5.00% 218.12 10.91 18' 2.12" 290.49 1:2.57
2> 54x20 72.90 5.26% 229.02 12.05 19' 1.02" 276.65 1:2.70
3> 54x19 76.74 5.56% 241.08 13.39 20' 1.08" 262.82 1:2.84
4> 54x18 81.00 5.88% 254.47 14.97 21' 2.47" 248.99 1:3.00
5> 54x17 85.76 6.25% 269.44 16.84 22' 5.44" 235.16 1:3.18
6> 54x16 91.12 6.67% 286.28 19.09 23'10.28" 221.32 1:3.38
7> 54x15 97.20 7.14% 305.36 21.81 25' 5.36" 207.49 1:3.60
8> 54x14 104.14 7.69% 327.17 25.17 27' 3.17" 193.66 1:3.86
9> 54x13 112.15 8.33% 352.34 29.36 29' 4.34" 179.83 1:4.15
10> 54x12 121.50 9.09% 381.70 34.70 31' 9.70" 165.99 1:4.50
11> 54x11 132.55 0.00% 416.40 0.00 34' 8.40" 152.16 1:4.91

MIDDLE GEAR
==============
Wheel Diameter: 27.00 inches
Gears: 32 11-12-13-14-15-16-17-18-19-20-21
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
1> 32x21 41.14 5.00% 129.25 6.46 10' 9.25" 490.20 1:1.52
2> 32x20 43.20 5.26% 135.72 7.14 11' 3.72" 466.85 1:1.60
3> 32x19 45.47 5.56% 142.86 7.94 11'10.86" 443.51 1:1.68
4> 32x18 48.00 5.88% 150.80 8.87 12' 6.80" 420.17 1:1.78
5> 32x17 50.82 6.25% 159.67 9.98 13' 3.67" 396.83 1:1.88
6> 32x16 54.00 6.67% 169.65 11.31 14' 1.65" 373.48 1:2.00
7> 32x15 57.60 7.14% 180.96 12.93 15' 0.96" 350.14 1:2.13
8> 32x14 61.71 7.69% 193.88 14.91 16' 1.88" 326.80 1:2.29
9> 32x13 66.46 8.33% 208.79 17.40 17' 4.79" 303.46 1:2.46
10> 32x12 72.00 9.09% 226.19 20.56 18'10.19" 280.11 1:2.67
11> 32x11 78.55 0.00% 246.76 0.00 20' 6.76" 256.77 1:2.91
---------------------------------------------------------------------------

LOW GEAR
=====================
Wheel Diameter: 27.00 inches
Gears: 16 11-12-13-14-15-16-17-18-19-20-21
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
1> 16x21 20.57 5.00% 64.63 3.23 5' 4.63" 980.40 1:0.76
2> 16x20 21.60 5.26% 67.86 3.57 5' 7.86" 933.71 1:0.80
3> 16x19 22.74 5.56% 71.43 3.97 5'11.43" 887.02 1:0.84
4> 16x18 24.00 5.88% 75.40 4.44 6' 3.40" 840.34 1:0.89
5> 16x17 25.41 6.25% 79.83 4.99 6' 7.83" 793.65 1:0.94
6> 16x16 27.00 6.67% 84.82 5.65 7' 0.82" 746.97 1:1.00
7> 16x15 28.80 7.14% 90.48 6.46 7' 6.48" 700.28 1:1.07
8> 16x14 30.86 7.69% 96.94 7.46 8' 0.94" 653.60 1:1.14
9> 16x13 33.23 8.33% 104.40 8.70 8' 8.40" 606.91 1:1.23
10> 16x12 36.00 9.09% 113.10 10.28 9' 5.10" 560.23 1:1.33
11> 16x11 39.27 0.00% 123.38 0.00 10' 3.38" 513.54 1:1.45


ALL RINGS
===================
Wheel Diameter: 27.00 inches
Gears: 16/32/54 11-12-13-14-15-16-17-18-19-20-21
---------------------------------------------------------------------------
SP CRxFW GI GIdf DI diff DF PRPM RT
---------------------------------------------------------------------------
1> 16x21 20.57 5.00% 64.63 3.23 5' 4.63" 980.40 1:0.76
2> 16x20 21.60 5.26% 67.86 3.57 5' 7.86" 933.71 1:0.80
3> 16x19 22.74 5.56% 71.43 3.97 5'11.43" 887.02 1:0.84
4> 16x18 24.00 5.88% 75.40 4.44 6' 3.40" 840.34 1:0.89
5> 16x17 25.41 6.25% 79.83 4.99 6' 7.83" 793.65 1:0.94
6> 16x16 27.00 6.67% 84.82 5.65 7' 0.82" 746.97 1:1.00
7> 16x15 28.80 7.14% 90.48 6.46 7' 6.48" 700.28 1:1.07
8> 16x14 30.86 7.69% 96.94 7.46 8' 0.94" 653.60 1:1.14
9> 16x13 33.23 8.33% 104.40 8.70 8' 8.40" 606.91 1:1.23
10> 16x12 36.00 9.09% 113.10 10.28 9' 5.10" 560.23 1:1.33
11> 16x11 39.27 4.76% 123.38 5.88 10' 3.38" 513.54 1:1.45
12> 32x21 41.14 5.00% 129.25 6.46 10' 9.25" 490.20 1:1.52
13> 32x20 43.20 5.26% 135.72 7.14 11' 3.72" 466.85 1:1.60
14> 32x19 45.47 5.56% 142.86 7.94 11'10.86" 443.51 1:1.68
15> 32x18 48.00 5.88% 150.80 8.87 12' 6.80" 420.17 1:1.78
16> 32x17 50.82 6.25% 159.67 9.98 13' 3.67" 396.83 1:1.88
17> 32x16 54.00 6.67% 169.65 11.31 14' 1.65" 373.48 1:2.00
18> 32x15 57.60 7.14% 180.96 12.93 15' 0.96" 350.14 1:2.13
19> 32x14 61.71 7.69% 193.88 14.91 16' 1.88" 326.80 1:2.29
20> 32x13 66.46 4.46% 208.79 9.32 17' 4.79" 303.46 1:2.46
21> 54x21 69.43 3.70% 218.12 8.08 18' 2.12" 290.49 1:2.57
22> 32x12 72.00 1.25% 226.19 2.83 18'10.19" 280.11 1:2.67
23> 54x20 72.90 5.26% 229.02 12.05 19' 1.02" 276.65 1:2.70
24> 54x19 76.74 2.36% 241.08 5.68 20' 1.08" 262.82 1:2.84
25> 32x11 78.55 3.12% 246.76 7.71 20' 6.76" 256.77 1:2.91
26> 54x18 81.00 5.88% 254.47 14.97 21' 2.47" 248.99 1:3.00
27> 54x17 85.76 6.25% 269.44 16.84 22' 5.44" 235.16 1:3.18
28> 54x16 91.12 6.67% 286.28 19.09 23'10.28" 221.32 1:3.38
29> 54x15 97.20 7.14% 305.36 21.81 25' 5.36" 207.49 1:3.60
30> 54x14 104.14 7.69% 327.17 25.17 27' 3.17" 193.66 1:3.86
31> 54x13 112.15 8.33% 352.34 29.36 29' 4.34" 179.83 1:4.15
32> 54x12 121.50 9.09% 381.70 34.70 31' 9.70" 165.99 1:4.50
33> 54x11 132.55 0.00% 416.40 0.00 34' 8.40" 152.16 1:4.91

How about throwing in the CV hub. Infinite adjustments.
http://www.sheldonbrown.com/harris/nuvinci.html

I thought it got a bad rap for losing cycling efficiency, I seem to recall it was about a 7% loss, but I don't have the links. but it's an idea

That may be solved now but not the 9+ pounds it weighs.

Interesting. Strange that they don't give the range in GI for the unit. Gut says weight and efficiency are deal killers.

Well, this saves me from starting a thread. I'm also a Sequoia owner who's thinking of a new bike with a compact/triple option. I did upgrade my Sequoia a couple years ago, trashing the Sora pieces and going to a 105 triple with 12-27 cassette. So I know what that feels like.

The bike I've got my eye on is a Synapse Carbon 5 that is available with the same 105 setup that I'm now using, or with a compact 54/30 and 12-25 cassette. From reading the posts here, I'm now thinking of going with the double, but maybe installing an almost-new 105 12-27 cassette that I happen to have. I hope this can be done without derailleur or chain-length issues.

In any case, I've almost never been in the 30/27 gear combo on the steepest hills that I'm likely to encounter, so the 34/27 low gear should be sufficient. Thanks for the excellent discussion -- this section always has good info without some of the stuff that goes on elsewhere.

Are you certain the compact crankset is a 50/30? Most are 50/34 or 50/36. You most likely will be able to use the 12-27 cassette without going to a long cage derailleur, chain length would be the only concern if it had been shortened.

Gear chart
 

Could you please explain this gearing chart? Most of the numbers make no sense to me.

Example: first line, 2130 622 Huh?
Second line: 26.7 30 39 50. That's 30 on the casette, 39 on the chainring for a result of 50 inches, right? What's the 26.7, then?
Third line and all the rest: 12 67 87 111. I think we are talking about a 12 tooth cluster but which is the number of teeth up front? Do they even make 67 tooth chainrings?

Thanks for the explanation.

It doesn't sound like a lot, but it's almost 10%. I've never understood compacts. Recumbents always want MORE range, and compacts give you less (compared to a triple, anyway...) I've softened my stance over the years, but I still wouldn't want one if a triple was available.

Oops -- it was a typo and I meant 50/34 (not 54/30!) as you pointed out. Thanks for the correction and info!

Well, I don't understand the standard triple these days with the 52/39/30. It seems to me that the 39 and 30 are too close together. I have heard that you can "cheat" and stick on a 28 instead of the 30. That way you can get close to the 1 to 1 gearing on chain ring and rear cog which is 27 chain inches.

The triple gives you a wider range. I think the compact double gives you gears that are almost as low and it will shift a tad better. Plus, many people feel that the triple has a certain air of "fredness". I like a triple for rides where there are long climbs like northern GA or out west in the mountain passes.

Here in Central FL, there isn't any hill in the state that I can't get up in my 39/24 out of the saddle and bonked. I think the steepest grade is 16% but for a very short distance.

It is not the 39 and 30 that are close together-It is the 52 and 39 that are too far apart if anything.

My first road bike had a triple with 52/42/30 fitted. I rarely used the 52 except when coasting downhill. That gave me the impetus to try a compact 50/34 and I liked it. 50 to 34 was a bit big but I soon adjusted to it. I decided I was going to set the TCR up with a triple and I got 50/39/30 rings. They do fall perfect for gear changes. I still can't pull the 52 but 50/12 and even on the flat is easy.

Steepest hill round here is 16% on the road and I use the compact on that. 34/27 and cadence is low by the end. But it is not the steepness that gets me the hills- It is the length. Get a hilly ride with plenty of 10 to 15% thrown in and about 3,000ft of climbing and the compact will knock me out. Hence the triple but for LOOOOOng climbs- I will use the triple with a 28 on it.

One (expensive) option for wide-range gears on a compact double....

I'm now upgrading my CX bike's SRAM 50-34 compact double with a XX RD and XX 11-36 cassette (11-12-14-16-18-21-24-28-32-36). I'll have a 122 inch high gear with the 50-11 and a 25 inch low gear with the 34-36. Not everyone needs such a low gear, but I'm planning on taking the bike on some trips where I'll be in the second or third of 90+ mile days in the western mountains and I want the safety net of having a bailout gear, especially with my bad knees.

The drawbacks (obviously) are the big jumps in the rear cogs (14%-17% typically), but this can be somewhat mitigated by finding an in-between gear on the other ring. Even with double-shifting, there is one "worst case" jump of about a 14% change in gearing right in the 14-15 mph cruising gears which may be bothersome on long gradual uphills, but such is the compromises one makes. If I had my druthers, I'd make the smallest cog on the back a 13 and tighten up the spacing to avoid the three-tooth jump from 18-21.

- Mark

I have both triples and a traditional 42/52 double. Shorter cages shift more quickly than medium or long cages. Otherwise, except for the noticable, if I want to notice it, lower Q factor, there are, for me, no major drawbacks to the triple other than an energy bar's difference in weight. The triple gives me a lovely cruising range in the middle ring for everything from rollers to strong tailwinds...with no double shifts. The last few climbs on that long ride, or that super steep pitch, are more comfortable on the granny. On climbs during days when the knees are stiff the granny is useful. Campy brifters with micro-adjust shift crisply enough and allow no instances of chain rub. DA bar-ends are also good for shifting triples.





At 62 and liking hilly rides, my triple gets good use. Several years ago, more governed by vanity and with healthier knees, I would have opted for the compact.

What about a compact double 46-36 cyclocross crankset? FSA makes cyclocross cranksets that are compatible with 9/10 speeds. These would work well for a long hilly ride (100+ miles). Cyclocross bikes are commonly used by tourers carrying modest loads.

Sure it will work, but with a narrower gear range than the typical 50-34 road compact double. I think the goal here is wider gearing to better match a triple, not narrower gearing.

- Mark

Look at the gear charts posted by Hermes. Compare the lowest gear combination you use now with the lowest offered by a 50-34 compact double. If you could achieve the same gear inches with a compact double as your current triple, you should be good to go.

Here's my personal experience. I have used the standard 52-39 cranksets with 12/25 or 12/27 cassettes for years on my road bikes, and it is pretty hilly where I ride. For commuting, the gearing seemed kind of high because my route is very hilly and I'm carrying much heavier loads. So when I built up a new touring frame for commuting last winter, I decided to use a compact double 50-34 w/ 12/27 cassette. The compact crank has been great, and I wouldn't hesitate to go that route again on my other road bikes. However, for loaded touring, I am not yet sure if the compact crank will provide low enough gearing. I'll have to determine that through trial and error.

Agonized the same way before I purchased my Roubaix. Finally went with the triple, and though I don't use the granny gear too often, when I do, I am very glad I have it.

Depends on what kind of range you are after. 11/27-36/46 is practically the same range as 12/25-34/50. The transitions between front rings would be much better with the 36/46 setup, but the 34/50 has more potential for lower and higher gearing by changing cassettes.

Adding a SRAM DualDrive to your existing drive train will give you a 0.73 underdrive and a 1.36 overdrive, while preserving all your current gears. It triples the effective number of chainrings you have. You have to be willing to put a third shifter on your handlebars, though.
http://www.prowheelbuilder.com/product.php?prod_id=332
(That's not to endorse the dealer, only to show the product.)

Interesting. It is another 2.6lbs/42 oz. I don't quite understand what underdrive and overdrive would do. How does that change the gear ratio or GI? 3 lbs, quite a bit of extra weight.

I can see that the lowest gear on the compact double that I'm looking at -- 34/27 -- is pretty much equivalent to the 2nd lowest gear on my current triple: 30/24. So the only thing I'll be giving up is the low-low 30/27 gear, which I've been in rarely and probably could have lived without it even then. Besides, the new bike will be much lighter and equipped for fast training rides instead of touring, so I really think I'll be OK with it.

And I'm keeping the old bike to use for what it's best for anyway.

I've switched everything over to a compact double jumping between a 12-25 and 12-27.
I rode a bike the other day that had a traditional 53/39 and it took me awhle to figure out what was wrong, why it felt soo strange.i
Another 2 cents pretty-soon you'll have a dime.

Why do people say that??? With a difference of 16 teeth between chainrings, a compact shifts about as poorly as a setup can while still being called marginally workable. All other things being equal, a system with 8-12 teeth between rings will shift much better than a compact.

Compared to a 30T granny ring, a compact gives up about 12% on its lowest gear. If you figure 5% per 'gear' that's over 2 gears you lose by going to a compact. If you never use less than third gear on a triple, and you never use your tallest gear either, then a compact makes sense for you. I use 'em all, though.

Let's use a compact 34/50 crankset as an example. With the direct drive, your chainrings are still 34/50 just like normal. If you shift the hub into underdrive, you effectively have a 24.8 tooth chainring and a 36.5 tooth chainring. Yes, it's not perfect integers, but the chain doesn't care because it's just a ratio. If you want to fly on a downhill, you shift into overdrive and your chainrings effectively become 46.2 teeth and 68 teeth. Duplicates? Sure. But whatever gear you need will be there somewhere.

I agree, the solution is not for weight weenies; it's for someone who needs a large range of gears.