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Compact double or triple on C&V bike?

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Compact double or triple on C&V bike?

Old 06-24-18, 05:43 AM
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Compact double or triple on C&V bike?

When setting up a C&V bike what are the pros/cons of running a compact double versus a triple? Triples are pretty much dead for modern bikes both for technical and financial reasons but there is a fine supply of excellent triples for C&V bikes. There are so many good triples that came stock on mountain bikes with 110/74 bcd chainrings and sugino still makes a square taper triple. Those triples can be run as a compact double (which is how I recently set up a 1985 cannondale ST 400). Plus there are other crank designs that work as a compact such as the stronglight 99 (and the SR copies of the 99) which lets you run as small as a 28 tooth chainring.

I think compacts make a lot of sense with 9 or more on the back but less so running 7 or fewer cogs on the back for two reasons. First, I find a 34 tooth chainring to be so so for general cruising around and spinning. The middle ring in a triple provides, I think, a better gear to spin on the flats since you typically run something larger than 34 teeth. Second, I find I can get a better climbing gear and narrow the jumps in gearing by going with a triple since you can typically run a smaller freewheel (i.e., one with smaller gearing jumps) in the rear with a triple and still get good climbing gears.

So how about you? When setting up a C&V bike for hill climbing and mountains, do you tend to run compact or a triple?

I'm curious. I spent some time thinking about this before I set up my 1985 Cannondale ST 400 with a compact (50/34 up front, 12-30 7 speed in the rear). I like the bike a lot and I think I like the gearing but everything else being equal I prefer a triple and I may yet rebuild the bike with a triple crank.

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Old 06-24-18, 05:55 AM
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While I agree that you can get closer ratios/gearing jumps with a triple, especially on 6-7 speed systems, I find them a little too finicky for everyday riding. Properly set up, a compact double with a six speed rear is the right tool for some jobs.
For example, my '88 Cannondale SR500 and '88 Bottecchia team record are both set up with a 50/34 and 12/28 (six and 7 speed, respectively) gearing. Around here, with our combination of step, short climbs and false flats, they have all of the range I really need- roughly 30 to 100 gear inches.

For longer, steeper climbs like The Dare, I'll use a 50/34 compact with a 9 or 10 speed 12-34 cassette. Closer ratios, smaller jumps but still easy to downshift to the small ring when you turn a corner and face a steep one.

But when the going gets really tough- like Eroica or Cino- a 48-36-24 triple is the real deal. For me, anyway.
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Old 06-24-18, 06:05 AM
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Originally Posted by rccardr View Post
While I agree that you can get closer ratios/gearing jumps with a triple, especially on 6-7 speed systems, I find them a little too finicky for everyday riding. Properly set up, a compact double with a six speed rear is the right tool for some jobs.
For example, my '88 Cannondale SR500 and '88 Bottecchia team record are both set up with a 50/34 and 12/28 (six and 7 speed, respectively) gearing. Around here, with our combination of step, short climbs and false flats, they have all of the range I really need- roughly 30 to 100 gear inches.

For longer, steeper climbs like The Dare, I'll use a 50/34 compact with a 9 or 10 speed 12-34 cassette. Closer ratios, smaller jumps but still easy to downshift to the small ring when you turn a corner and face a steep one.

But when the going gets really tough- like Eroica or Cino- a 48-36-24 triple is the real deal. For me, anyway.
Some people might think the Dairyland Dare (almost 6000 ft of climbing for the 150k) is the real deal. Just sayin. . . .
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Old 06-24-18, 06:21 AM
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FWIW triples were the go-to choice for LD club riders and tourists "back when" on a P-15 Paramount or Trek 720:
On a C&V machine that is intended for long rides in challenging terrain today: Same, same.

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Old 06-24-18, 06:51 AM
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Back when 6-speed freewheels were rare, I did several 2x5 to 3x5 conversions in order to cover the range I needed (low to mid 40s to mid 90s gear inches) while maintaining about a 6 to 7 percent ratiometric progression, which is roughly the equivalent of a 3-tooth chainring drop or half of a 2-to-3-tooth rear cog drop. I was fond of 1/3-step, e.g. 48-45-42/13-16-19-23-26, which required only long stack bolts and a long spindle -- no special spiders and worked with a standard 144mm BCD road double crankset. A 2x6 -- preferably 2x7 -- half-step or 1.5-step can give me the range I want without widening the ratio steps too far. The last road triple I ran was a tight 3x6 half-step-plus-granny -- 48-45-34/13-15-17-19-21-24, which worked well with a short-cage SunTour Cyclone II rear derailleur and a standard road double front derailleur.

The mountain bike needs an additional low range of gears and always gets some variation on a 1.5-step-plus-granny, either 3x7 or 3x8. I currently run 48-40-24/12-13-15-17-19-21-24-28.
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Old 06-24-18, 08:44 AM
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Been running half step and granny on everything lately. I think I'm just old though.
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Old 06-24-18, 09:06 AM
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[QUOTE=rccardr;20409584]While I agree that you can get closer ratios/gearing jumps with a triple, especially on 6-7 speed systems, I find them a little too finicky for everyday riding. Properly set up, a compact double with a six speed rear is the right tool for some jobs. .[/QUOTE

Double or triple is a matter of personal preference, of course. But Iím always puzzled by those who say that triples are too difficult to set up or to shift. Iíve set up and ridden with triples since the 1970s, with friction shifters and now with brifters. I now have 4 bikes with friction shifting triples and three with brifter triples. I just donít see the difficulty; and I do see the benefits.
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Old 06-24-18, 11:47 AM
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I suspect people often miss the essential point on the subject. So here's what I think, without going into lots of numbers which sort of obscure the point.

First, a disclaimer: Though we have a 1-1/2 step crossover 3x5 triple on our tandem which works well for us, I've set up all my solo bikes with doubles, generally compact but not necessarily.

I start by finding a way to get whatever low gear I need as essential. After that, whenever I contemplate double vs. triple I come up to the same conclusion: The determining factors are high gear and gear spacings. Do I need 105 gear-inches? Or 90? Or what? So what should the next largest chainring be? If I can get an acceptable high gear and decent crossover spacings with just one more ring, what would be gained by using a triple instead? Really, nothing. Another ring would let the middle ring be smaller than the big ring on a double, and the triple's big ring would be bigger than the big ring on a double. But if the double's high gear and intervals are fine already, then there is no real benefit. I'd be carrying the extra ring with nothing gained, and the front shift would be three-state instead of binary.

The reason the triple works on the tandem is that we really do use the full range of gearing, slow uphill, fast down even on gentle downhills. My solo bikes don't have quite as low a low, and I don't need so much high either.
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Old 06-24-18, 03:09 PM
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I've got triples on two bikes and since I am cheap they will stay that way and running them in friction mode they work fine. If I was doing a from scratch build, however, I would probably go with a 46/30 compact, the older I get the less I care about top end speed and a nice 30/32/34 big cog in back allows me to climb most hills in my neighborhood. YMMV
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Old 06-24-18, 03:38 PM
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I like the Holdsworth/ IRD 48-34 compact cranks. They have a vintage Campy / Sugino look with drilled rings. Have on 2 vintage road bikes. Velo Orange are similar... made by IRD as well, I think.

I have Shimano 46-36-28 triple on my Shogun tourer and a Campy Daytona w/ triplizer on my Trek 660. Everything is 5 or 6 speed rear w/ friction shifters and vintage derailleurs.
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Old 06-24-18, 03:45 PM
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I've totally changed my thinking on this subject.

Recently I picked up my first plastic bike (15 lb with ultralight wheels) and was astounded by the responsiveness and ease that thing moved forward, even on big climbs vs lugging my 23+ lb Trek with the triple around.

I just put the Trek on a diet and got her to below 19 lbs, half of that in crank and wheels, the remainder selecting lighter components from the parts bin. Although the Trek is arguably not fully C+V with a carbon crank and ultralight Bitex hubs, but I kept the downtube shifters.

So I'd also factor in the total weight of the bike into the equation as well.

But I'm with @rccardr in keeping the super low triple on my Peugeot for vintage events.
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Old 06-24-18, 07:42 PM
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Shrugs shoulders.
I have lots of bikes. Different tools for different jobs. Compact doubles. Standard doubles.
Sure, I have bikes with triples, but they are intended to be tools for jobs where triples are required. For me. YMMV
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Old 06-24-18, 11:20 PM
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For me, Mr. Triple is my friend, and my friend is on everything except my Eroica bike, and I'd like to make that a triple, too.
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Old 06-24-18, 11:58 PM
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My desired high gear and needed low gear can, indeed, be accommodated by a compact double, but when I look at the gearing ranges I use the most (in my area with lots of steep hills) and compare to how I’d actually be riding such a double, the most used gears would be at the extremes for both rings, meaning lots of double shifts and cross-chaining. My 8-speed Ergo-shifted triples are very simply to set up, which I know is not always as likely with the much more prevalent modern systems.

That said, my wife loves the shifting on her newish Independent Fabrications bike with its 46-36 double, but it took an 11-40 cassette (11-speed, needed for the required hydraulic discs) to get the same range. And she mostly treats it like a 1X11, rarely shifting off the 36T ring. I learned long ago to make sure she’s a happy rider, whatever that takes.
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Old 06-25-18, 01:01 AM
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I've never understood what people are referring to when they talk about triples having finicky shifting. The mode of operation is exactly the same as with doubles, and because the gear jumps are usually smaller, shifts can catch just as consistently and resolve even faster. In addition, the smaller shifts require fewer rear shifts to compensate, assuming a similar cassette, so the double-shifts are faster and less disruptive. Furthermore, since you can pick a middle ring which centers the cluster's tight ratios around your typical speeds, triples make it easier to avoid a split range, where you spend lots of time either too small-small or too big-big; so you also might not need to make as many front shifts in the first place.
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Old 06-25-18, 05:20 AM
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Originally Posted by rccardr View Post

Sure, I have bikes with triples, but they are intended to be tools for jobs where triples are required. For me. YMMV
+1. The right tool for some jobs.

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Old 06-25-18, 08:13 AM
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I prefer triples because I can skew the gearing one way or another easier with a triple. I can stack a lot of gears/choices at the point where I want. With a triple, you have 2 ring choices for most every cog except the 2 on the ends of the gear range. Some days, one choice might feel better than the other. You don't have those choices with a compact. All you can do is increase/decrease your range with cassette/ring changes. You still will have the same shifting patterns/choices, though.

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Old 06-25-18, 08:28 AM
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A triple chainring is not finicky if you have a trimmable front derailleur, preferably entirely non-indexed.

When I use the 48-40-28 setup on my mountain bike, I use the middle and outer rings on-road as a 1.5-step, and the middle and inner offroad as a crossover. The only time it gets at all finicky is when I swap in the 24-tooth inner, because the 24-to-40 shift does require a small amount of finesse and absence of load on the chain, but that's all just part of traditional proper shifting technique, anyway.
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Old 06-25-18, 08:42 AM
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Originally Posted by John E View Post
A triple chainring is not finicky if you have a trimmable front derailleur, preferably entirely non-indexed.

When I use the 48-40-28 setup on my mountain bike, I use the middle and outer rings on-road as a 1.5-step, and the middle and inner offroad as a crossover. The only time it gets at all finicky is when I swap in the 24-tooth inner, because the 24-to-40 shift does require a small amount of finesse and absence of load on the chain, but that's all just part of traditional proper shifting technique, anyway.
There you go. As I said, you can customize your gearing and shifting patterns with a triple. I have one ride each year that I go with a 50/36/28. The rest of the year, I am running a 52/42/30 or 50/40/28.
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Old 06-25-18, 08:43 AM
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Used a triple with a 52t <C> GS chain ring and a 222 diameter <C> cross chain.guard as the outer

on a Gippiemme triple with a 36t 3rd chainring on my AlAn in the 80's <C> Triple BB..

Polished and excellent, condition will sell (PM) bike frame recycled after it cracked its "Lugs"

Its replacement an RB1, got the components , and a newer 50,40, [24, replacing the 30] 'race triple'..





..
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Old 06-25-18, 10:48 AM
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How is "compact double" defined? Sheldon Brown says
... permits the use of smaller chainrings than will fit with the common 130 mm B.C.D.
and indicates down to 33 teeth. What do people use as a compact double? I had a vague impression from notes which have crossed my field of vision that 48-38 was common, but maybe not?

I ask because I'm tweaking the gearing on my Schwinn Volare to make it just a bit more amenable to hills (Apple Cider Century is coming in September; I am unlikely to ride the Dairyland Date this year). It has first gen DA crank (130 BCD) which I think will be good enough for my needs. I've got a line on some 48T and 49T big rings and a 39T small ring. I just bought a 13-24 SunTour Ultra-6 freewheel to replace the five-speed D-A freewheel with (I think) 21T big cog. That will get me a 45-inch low gear vs. the 55-inch low I have now. That should be fine for a couple more years.
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Old 06-25-18, 10:59 AM
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Originally Posted by smontanaro View Post
How is "compact double" defined? Sheldon Brown says
... permits the use of smaller chainrings than will fit with the common 130 mm B.C.D.
and indicates down to 33 teeth. What do people use as a compact double? I had a vague impression from notes which have crossed my field of vision that 48-38 was common, but maybe not?

I ask because I'm tweaking the gearing on my Schwinn Volare to make it just a bit more amenable to hills (Apple Cider Century is coming in September; I am unlikely to ride the Dairyland Date this year). It has first gen DA crank (130 BCD) which I think will be good enough for my needs. I've got a line on some 48T and 49T big rings and a 39T small ring. I just bought a 13-24 SunTour Ultra-6 freewheel to replace the five-speed D-A freewheel with (I think) 21T big cog. That will get me a 45-inch low gear vs. the 55-inch low I have now. That should be fine for a couple more years.
130 bcd is a road double and it lets you get down, as you point down, to 39 teeth. That was an improvement over the older road "standard" (really campy) of 144 bcd which let you get down to 42 teeth. The stronglight 93 is a pretty cool alternative since you can get down to 37 teeth which sort of puts it into compact range, 122 BCD Conventional Chainring, 37 Teeth

By compact I was thinking of 110 bcd cranks which lets you get down to 34 teeth. These are readily available for vintage bikes since so many mtb triples were made (110/74 bcd). You can get "smaller" compacts like TA, stronglight 99, etc.
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Old 06-25-18, 11:53 AM
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Originally Posted by smontanaro View Post
How is "compact double" defined?
In the current road vernacular, if it's being used with a high degree of specificity, "compact double" means 50-34.

53-39 is now a "standard double" despite not being anywhere near standard on new road bikes. 52-36 is a "mid-compact", and smaller ones like 48-32 sometimes get called "sub-compact."

The cycling world has a bizarre obsession with the word "compact," and an inexplicable fear of describing products with descriptive numbers.

I had a vague impression from notes which have crossed my field of vision that 48-38 was common, but maybe not?
46-36 is popular for cyclocross bikes with doubles. 48-38 is an unusual combination.
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Old 06-25-18, 12:57 PM
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Originally Posted by HTupolev View Post
In the current road vernacular, if it's being used with a high degree of specificity, "compact double" means 50-34.
Lots of cranks on the market are 48-34 and designated compact double. Check out Holdsworth or VeloOrange, for example. 110BCD lets you choose whatever smaller rings you want, but when sold as a crankset 48-34 isn't uncommon.
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Old 06-25-18, 01:20 PM
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Location: Boston-ish, MA
Posts: 13,259

Bikes: 73 Raleigh Carlton Gran Sport, 72 Peugeot UO-8, 82 Peugeot TH8, 87 Bianchi Brava, 76? Masi Grand Criterium, 87 Centurion Ironman Expert, 74 Motobecane Champion Team, 86 & 77 Gazelle champion mondial, 81? Grandis, 82? Tommasini, 83 Peugeot PFN10

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I keep thinking about one more consideration after I sign off. (Duh, what was I about to type? Oh yeah, I remember.)

The spacing between the various rings and FD cage could be problematic. You position your FD to give maybe 1mm clearance between outer cage plate and big ring, but you get get whatever it is on the smaller ring. Shifting the chain from big to small is easy, pulling it from small to big requires the big ring to catch it firmly enough to lift it up. That's (one reason) why the ring-cage spacing can matter.

The thing about a middle chainring is that the shifting mechanism from small to middle works the same way as small to big on a double, but now your cage is much further from the destination ring. It's like shifting a double but with the FD misplaced too high. And depending on the rings' sizes and chain flexibility, shifting to the middle ring could make the chain contact the big ring too, thus causing a double shift. For example with a triple set up as 26, 30, 52 shifting small to middle could be nearly impossible. (Of course that would be an unlikely choice of rings.)

I'm not saying triple can't be made to work, especially as we have a nice one on our tandem that works well. I'm saying that you have to be aware of the possible issue. Whenever I contemplate the choice of compact double vs. triple, this is yet another factor. Why set up a middle ring with this possible issue when I can position the FD for a double easily? Perhaps this is one big reason some people find a triple hard to set up.
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