compact vs triple chain ring

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Anonymous's picture

Anyone have good advice for someone who has been riding a double chain ring for years, but is buying a new bike and not getting any younger! I don't do any serious racing (just biathlons and long group rides - A19 rider) but want to preserve the knees. What do I gain from moving from a double to a compact or between a compact and a triple? Gearing will be a 10 speed 12/27 cassette and 34/50 crank on the compact.


Anonymous's picture
Steve (not verified)
hope this helps
Anonymous's picture
jc (not verified)
Try these two
Anonymous's picture
Carol (not verified)
Another option... a compact triple (30/40/50). The middle ring is very close to the 39 you're probably used to on a standard double. You'll be able to stay in that ring for most of the hills you'll do around here (and when you can stay in the 40-tooth middle ring, you don't loose momentum), but you'll have that knee-saving 30 for when you encounter something really steep or when you've already done 80 miles and you still have to climb Walnut.

I have the compact triple with a 13-29 cassette, and even with arthritic knees, it gets me wherever I need to go.

Anonymous's picture
Neile (not verified)
You can also swap out the 30T for as low as a 24T

"That way you can still use a small, close ratio rear cassette but still have your ""bale out"" option.

If you do this, have the shop add a ""chain shark"" to the seat tube to keep from de-chaining going from middle to low gear.


Anonymous's picture
April (not verified)

">If you do this, have the shop add a ""chain shark"" to the seat tube to keep from de-chaining going from middle to low gear.<

Why do you need that?

Why is going from 40 to 24 more problematic than going from 50 to 34?

Anonymous's picture
Neile (not verified)
"""Why do you need that?"""

"Can't say ""why"", but jumping that many teeth (42-24) on a triple was a problem and the shark (or n-gear as below ... same idea) solved it.

Maybe 'cause the 24T is so small ... or maybe 'cause it's not needed on a double ..."

Anonymous's picture
Bill Vojtech (not verified)

I've got a double with a chain shark. It came that way from the shop that set it up. I don't know if they had a problem getting the chain to stay on or if they just do it to play it safe. I've seen doubles drop the chain, but never on that bike.

I'd put one on any bike I set up from now on, except a fixed gear bike.

I tried to set up a touring bike with a 48-38-26 triple. The rings generally don't come with the ramps and pins that the factory triples come with, so shifting was not as smooth. Also, the touring shifters are made to work with the 53-42-34 that comes standard on most triples.

After years of searching I got a middle ring ring with pins to help shifting, but it still does not shift as well as the factory set ups.

If you go for a triple use a stock set up.

As a result, when I got my Seven, I went with a double 48-38 chainrings with 26t on the freehub. Nice and simple– and low enough for me if I'm not touring with packs.

Anonymous's picture
Sandy (not verified)

Thank you so much - this makes sense. I will speak to the shop and see what they say.

Much appreciated!!!

Anonymous's picture
jc (not verified)

Hi Sandy,

I've been using this little gizmo with my compact set-up and haven't dropped the chain yet. Works like a charm.

Anonymous's picture
sage (not verified)

Sandy -- I just bought a new bike and was confronted with the same question you have - whether to go with a compact double or triple or stay with the double. I ended up getting a compact double - a 10 speed 12/27 cassette and 34/50 crank on the compact and I really like it. It helps on tough hill climbs and you don't really lose much on the downhills.

Anonymous's picture
george (not verified)

Get a 53-39 standard double up front with a 13-29 cassette on the back. This gives you a lower ratio for the lowest gear than a triple with a standard cassette, but still gives you enough oomph at the high end:

Lowest gear with a double & large cassette = 39/29 = 1.344
Lowest gear with a tripe & standard cassette = 34/25 = 1.36

Anonymous's picture
Sandy (not verified)

Thank you for your reply.

I really like having that extra gear for riding super fast and pulling the group on the flats and downhills, so was concerned about not having that ability. And then am wondering if the compact would actually be enough for those tough climbs out of town (Berkshires, etc) Have you had a chance to experiment on both extremes yet? I am trying to calculate the exact gain in cogs/gears for hill climbing and seeing if it is worth losing the downhill cog. Am so curious to hear your thoughts. Thank you!

Anonymous's picture
Neile (not verified)

"""I really like having that extra gear for riding super fast and pulling the group on the flats and downhills.""

Just what I need. Where can I order one?"

Anonymous's picture
Evan Marks (not verified)
One data point (edit)

33x48 crankset, 12-30 cassette: most of the range of a triple w/o the clunky front shifting. Low gear for an asthmatic's pathetic climbing ability, high gear bigger than said asthmatic can push on the flats.

33t chainring from TA at (most shops will tell you 34t is the smallest chainring for a compact).

Cassette kludged together from a 12-27 Shimano or 12-26 SRAM 9-speed - put on a 30t cog followed by the rest of the cassette minus the 14. Works perfectly with a DuraAce double rear derailer (except for that occasional 13 to 15 shift hangup).

Edit: use a gear chart to make direct comparisons:

Anonymous's picture
Etoain Shrdlu (not verified)
Gear you!

">> Low gear for an asthmatic's pathetic climbing ability, high gear bigger than said asthmatic can push on the flats.<<

On behalf of asthmatics everywhere I thank you for the gratuitous insult. There are other reasons one might choose to have a triple, but I won't trouble your pathetic brain with an education.

""Some people have pathetic social skills. If Marshall Tito chooses to liquidate them, who am I to protest?""
--Emily Posternack

Your Pal,
Etoain Shrdlu"

Anonymous's picture
Evan Marks (not verified)
Did you think I was talking about you?

You flatter yourself, but you're welcome nevertheless.

Anonymous's picture
Fred Steinberg (not verified)
Compact double vs triple chainrings

All gearing setups are compromises against age, injury, expense and maybe ego. Compact gearing loses gearing at one or both ends of the gearing spectrum. A triple will provide a lower low and/or a higher high and tighter gearing in between.

A powerful rider can manage a compact gearng's wide ratio gearing but if you do fast paceline rides you need power to keep the pace when the gearing isn't there. You'll be spinning out or burning your quads to maintain the pace.

STI and ERGO shifters make the double shifting (front chainrings) required to compensate for wider gearing in the rear cassette manageable, but there will be much more front chainring shifting to compensate for the big gear jumps.

Obviously I'm a proponent of close ratio cassettes and triple chainrings.

A standard compact setup of 34x50 12-27 will provide a gear inch range* of 34 to 112.5 - not low gearing in my book. Even Evan's problematical customized cassette provides a 29.7 to 108 gear inch range. Carol's example of Campy lowest standard gearing setup of 30/40/50 w/13-29 will provide a 27.9 to 103.8 range. A 30/40/50 w/12-25 provides a 32.4 - 112.5.

I've replace the 30t in Campy 30/40/50 with 26 and 28T chainrings for even better gearing, a simple change. A 26/40/50 with 12-25 cassette provides a 28 to 112 range; an 11-23 provides a 30.5 to 122.7 range. (Note: Campy's ERGO brain doesn't handle chainrings smaller than 30T).

Shimano apparently doesn't provide 40/50 chainrings options making such improvements impossible.

If you want low gearing get a (Campy) triple!

To see the impact of wider vs tighter gearing you can build a matrix using the formula: chainring size x 27 / cassette cog to compare the gear jumps a a specific setup.
Then evaluate that against your riding style and bias towards the low end, the basis of this discussion in the first place.

All configurations are subject to a chain drop. There are inexpensive Chaindogs, Chainwatchers, etc which keep the chain off the bottom bracket, which seems to plague triple setups the most.

Anonymous's picture
Evan Marks (not verified)
online gear calculator

Sheldon Brown to the rescue:

Anonymous's picture
af (not verified)
low gears with Shimano

"As Sheldon Brown discusses on his web site, you can use Shimano mtb cassettes for wide range gearing and substitute some smaller cogs to make your own ""custom"" setup so as not to lose closer spacing at the high end. In that respect, Shimano has many more low gear choices than Campy.

Also, the chain catcher devices won't work on many carbon or ti frames with a wide down tube, because they can't be placed low enough on the seat tube (they all go below the fdr)."

Anonymous's picture
Hector (not verified)
Compact Crank is fine

I would go with a compact crank. Unless you really can't climb, a 34/27 should be enough to get you up any hill around here and a 50/12 will be enough to get you down any hill and still feel the force of the pedals. Let's not make this a federal case, lol. Good luck with whatever you choose.

Anonymous's picture
Russ (not verified)
Campy Standard

Over the years I've had enough chain slippage and general up and down shifting problems with my Shimano triple (also general dissatisfaction with the 42t middle ring) so that I leapt at the chance to get a compact double last year. I wound up with a mix of a standard Campy 13/29 10-speed cassette and a standard FSA 50/34 carbon crank and rings, which comes pretty close to low enough for anything I could ever climb in the 30-27 combination on my old triple and is available pretty much everywhere. When I looked up the ratios, seems to me the 30-27 was smaller by maybe a gear inch. (I've tried some of the same hills in northern Westchester/Putnam on both the triple and the compact--and Keeler Lane and Joe's Hill hurt about the same, either way.) After a certain age, the high end doesn't seem to matter so much. I can't remember the last time I tried to spin out the 52-12 on one of my other bikes--if I could do it now, I'd be going too fast. With the compact, I'm happy to bear an occasional clunk and clang as I change rings in exchange for the security and simplicity of the double. For sure, the 10-speed offers plenty of close cog spacing at the high end--it's continuous from 13-17, 19, 21, 24, 26, 29--and I find it comfortable to ride the 50 ring with a mid to largish cog up most grades of reasonable length (.5 mile?) and modest steepness (3-4%?). To the extent these thoughts might influence anyone, bear in mind that, unlike some of the obvious gearheads who've already commented (and whose skills are more advanced and views are much more sophisticated), I don't like to fiddle with dirty chains and fuss with complicated derailleurs.

Anonymous's picture
Karol (not verified)
spinning out

"""A powerful rider can manage a compact gearng's wide ratio gearing but if you do fast paceline rides you need power to keep the pace when the gearing isn't there. You'll be spinning out or burning your quads to maintain the pace.""

Hi Fred,

Can you explain this to me? So if you go from the standard 39/53 chainring with 12/25 cassette to 34/50 compact and 11/23 cassette would I be spinning more on flats and burning out?


Anonymous's picture
Bill Vojtech (not verified)
FSA rings for Shimano cranks

"Fred wrote:
""Shimano apparently doesn't provide 40/50 chainrings options making such improvements impossible"".

Not impossible. FSA rings can fit Shimano cranks, (and FSA makes very nice cranks that they fit, too).

They don't seem to make a 40t, but they do make a 38t and a 39t. And that's even better because it's a little lower.

I've never understood why bikes come so overgeared these days. When I started riding (A rides) we commonly used 52t x 14t high gear of just over 100"". I never remember a downhill or paceline where I outpedaled a 100"" gear. With the 11t or 12t cassettes today's bikes come with and the 53t or 54t chainrings you get a high between 119""-132"". That's just excessive unless you're in the TdF, (maybe even then).

I wanted about a 10t difference between my chainrings and I wanted a fairly low gear for climbing, so I went with a 38t small ring and a 48t big ring. With a 12t small cog on the cassette I still get a 108"" gear, which is only good on significant downhills.


Anonymous's picture
Stephen Crowe (not verified)
Newly converted

After riding for a year with a 39x50 crank, I finally got religion last week and bought a genuine compact crank (34x50).

It's a real pleasure on long, hilly routes and plenty fast for most A rides that we offer as a club.

With Basso riding in grand tours on a compact crank and standing on the podium, what do recreational riders need with 39x53 chainrings?

Anonymous's picture
Mordecai Silver (not verified)
I agree

"Stephen Crowe wrote: ""What do recreational riders need with 39x53 chainrings?""

True, I don't like them either. Too large a gap. I prefer 52/42.

If Basso uses a compact crank, it's only in the mountains. He doesn't use one in rolling terrain.

In rolling but not mountainous terrain like ours, a compact requires too much double shifting. With a compact, a 50x21 is about 64 inches, and a 34x14 is about 66. That's right in the middle of a very useful range. With a triple, on the other hand, especially with a 42t middle ring, you can just shift up and down on the back for rollers, staying in the middle ring all the time.

The true religion of the gear-freak is half-step plus granny gearing. The high priest is Frank Berto. I'm proud to be a member (50/46/30, 14-28). For double-chainring crossover gearing, I like 52/42, 13-25."

Anonymous's picture
Stephen Crowe (not verified)
Hudson Valley

"Good point. Basso only uses his compact in the mountains and that's really where a compact is most at home.

For me, though, the compact has proved pretty versatile. I like it on rollers and steep climbs. I enjoy riding in the Hudson River Valley and it's pretty easy to find some challenging hills there. Last week's ""Harriman Hell"" ride contained nearly 7,000 ft. of climbing and that was the ""short"" version of the ride.

Also, the double shifting (front and rear derailleurs) might be slightly less of an issue with Campy, which allows you to skip past several cogs at once if you need to make a fast transition.

The occasional double shift has to date seemed like a fair trade-off for being able to spin up some pretty formidable hills, like Mine Road just north of Harriman, at 85-90 rpm. I'm not sure that I'm climbing any faster but my legs feel a heck of lot better at the end of 90-mile ride!"

Anonymous's picture
Chris Hartmann (not verified)
Which Compact crankset?

I have a 9 speed Campy Veloce setup on my bike. Any recommendations on which compact crank I should purchase? I also would lile to install this myself. Do I need to change the linkage on the chain or anything else? Do I also need a new derailler?

Anonymous's picture
Fred Steinberg (not verified)
try 13x28 cassette any 44x50 cranset........

......will get you a 41-104 gearing range.
You may need a long cage rear dereileur to handle that 28t cog. Any 44x55 crank would do. Try to get a crank that will work with your existing Bottom Bracket (BB) spindle and is the correct type, splined vs square spindle.

I've noted that the ages, strengths, riding styles of the contributors to this thread vary widely. There is really no baseline as to what is adequate low gearing.

To me adequatelow gearing means having a low gear that can get you up just about any hill anywhere. Mohonk Mountain with 75 miles on your legs on a hot summer day, not just State Line hill or Booth returning from Nyack.

Everything is relative.

Feel free to email me for further discussion.

Anonymous's picture
David Hallerman (not verified)
So-Called Mt. Cassettes Help So Much

"As Fred wrote, a ""26/40/50 with 12-25 cassette provides a 28 to 112 range,"" which is a very nice range.

I get similar gearing with 48/34 chainrings matched to an 11x32 cassette, which provides a 29 to 118 range. Or try those same 48/34 rings with a 12x34 cassette, giving a 27 to 108 range.

Of course, those cassettes require a Shimano ""mountain"" rear derailleur, such as the well-made Deore XT. But that mech works perfectly well with either Shimano STI shifters or Campy Ergo shifters (which require a JTek ShiftMate that gives perfect shifting with Campy/Shimano mix-and-match drivetrains).

That's my favorite setup now: The easier shifting of a double up front, the wide range of a Shimano mountain cassette in the rear, and the comfort and better (IMO) ergonomics of a Campy Ergo brifter.

Heck, even a standard 53/39 crankset matched with a 12x34 cassette gives a 31 to 119 range.

Such a setup might not work for many A level riders, but could be fine for the rest of us.

David, who says if you're interested check out the JTek Engineering website for their great gizmo


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