WheresWaldo

I am just curious about all the fuss over compact cranks. Why would you choose a compact over a triple? Conversely, why would you want a triple over a compact crank?

It's too bad this forum software deosn't allow polling.

cs1

Good question, the difference for the average rider to switch to a compact is minimal at best. With a 26 or 30 tooth low chainring the triple can be geared lower, which is what it's for.

Tim

Don Cook

My thoughts are that a compact conversion makes the most sense for those double riders with a traditional 53/39 setup. It provides (for most riders) a much more usable range of ratios. As for a person that presently has a tripple, it makes no practical sense to go to a double, since their tripple is already offering a wider range of usable gears than even a compact double would.

WheresWaldo

So let's say we are starting out with a double, now the choices are going to a triple or using a compact.

GuitarWizard

It saves weight, and saves having to upgrade your entire drivetrain. Not to mention, going from a 39x25 low (41 inch gear) to a 34x27 low (33 inch gear) should be more than adequate for your average recreational cyclist in fairly hilly areas, or a lightly loaded bike. Obviously, for touring, mega-steep mountaineous country, and those who need a little more "help", a triple is the better choice.

I will probably be upgrading my 5200 to a compact at some point this season, mainly for brevet/randonnee riding. I don't know about you, but riding a 53x39 ring and 12x25 cassette with nearly 40,000 vertical feet of climbing in under 4 days, as well as carrying a light load would not be very "knee friendly". A compact drivetrain is a good solution. Again, not the right solution for everyone, but it is for me. The other benefit of them is that some people may find the 50T ring more usable in more situations than a 53T ring.

Grasschopper

Personally I switched to the compact double from a triple. When I made the change I was going from a 52/42/30 crank with a 12-25 cassette. The new setup was a 50/34 compact with a 12-27 cassette. This gave me nearly as low of gearing as the triple setup with a little loss of on the high end...which as a non racer I was never using anyway. I soon found out that I was not using the 30-37 combo and have since switched to a 12-25 in the back.

I find that I don't have to shift the FD nearly as much as I did in the past which is a nice thing...I also have about the same number of usable gears (this assumes no major cross chaining with the triple). So it may be a little lighter...that isn't the real reason I did it....I like the shifting in inthe front a LOT better. IMO the compact double is a great solution for the majority of the recreational cyclists out there. Sure the 53/39 is ok for a racer who uses an 11-23 but as has been stated several times a compact with an 11-23 is lighter and gets you very similar gearing to a 53/39 with a 12-25.

But whatever...ride whatever makes you happy....that's what it is all about.

bbattle

It depends on how fit you are and how many hills you have to climb. Compared to the double, the compact loses a bit off the top end but gives you more low gears. I've got a compact and I can't spin 100 rpm in the top gears so I'm not losing anything on that end yet I sure appreciate the lower gearing when climbing.

Compared to a triple, the compact goes almost as low and almost as high or just as high. Fewer redundant gears, less shifting, less weight.

One advantage of the triple up front is that you can use a tight cassette in the rear for smooth upshifting while still having a wide range of gears for flats and climbs. 50-34 compact with a 11-23 won't give you the range of a 50-40-30 triple with a 11-23. Instead, throw on a 12-27 with that compact.

If you've got a double, I'd suggest the compact over the triple unless you are really struggling up the long climbs and the engine is already fit and lean.

CyLowe97

I may be wrong on this one, but if you have a 53/39 double, going to a compact will not require a new front or rear derailluer?

Or does changing from double to triple affect the brifters? That's an expensive change, if so.

Grasschopper

No need for new derailleurs going from a 53/39 to a 50/34(or 36) other than properly positioning the FD.

Double to triple only is an issue if you have the Shimano DA, or Ultegra 10 speed double brifters. Going the other way is not an issue.

steve_wmn

Hmm, have we ever discussed this before? No, not this month.

OK, I use a triple and I don't think I'd swap it for a compact double even if I had the disposable income. I find myself on the 42 tooth chain ring 90% of the time, running through a 12-25 cassette from about the 13 tooth to the 23 tooth on most terrain. On rare occasions I'll drop down to the 30 tooth chainring for a steep climb. On even rarer occasions I'll find a descent where I feel a need to go higher than a 42/13. That's what I get for living in Minnesota.

When I plot out the gears I actually use and look at equivalent gears on a compact I see the possibility of a lot more front shifting or cross-chaining as my favorite gears are closer to the 34/12 or 50/25 options. But I'll admit that compact doubles are a lot sexier than a triple and I might go with one in an OCP moment.

MichaelW

I fitted a Stronglight Escapade to my commuter bike and have altered it from a compact double to a triple to a single according to the conditions.

rrobins

I like using my Compact. I think it has made me a stronger rider. I spend most of my time in my 50 and will only shift to my smaller 34 when going up a hill. I came from a triple and really can not fathom why it took me so long to switch! IF you can afford it do it. It will make you a stronger rider..

jschen

I'm not in Minnesota, so I don't stay in the 42t chain ring as much, but for the same reason, I'm keeping my triple. It's nice that my cruising speed is right in the middle of my 42t gears, so I don't shift chainrings unless there's a meaningful grade. I don't use my 30t on my commuter bike, but since it's also my backup road bike, it's nice to have the granny ring.

So I think there's two reasons I might make the switch down the road. (1) I get fast enough to cruise in the middle of a 50t chain ring. (2) I get a separate climbing bike, in which case I'd do it to save weight (and would be in the 34t chain ring most of the time anyway).

Corsaire

I did the switch (from Ultegra Triple to FSA Compact pro elite) over the holidays, will never look back, I love it. I like the simplycity and efficiency that gives me, besides the weight savings.
Down gearing wise, it's very close to a triple in my lowest 34/27, and I find myself using it only in long steep grades, if any.
Hope that helps,
Corsaire

roadfix

For me personally, a triple makes sense on my mountain and touring bikes, where all I need is a compact double on my road bike which weighs a good 10 lbs less. If compacts were not available as they are today my only other option for lower gearing on my road bike would have been to go with a triple setup, as I personally need at least mid-30 gear inches or lower for long sustained climbs.

feltdude

The shifting is far smoother on a compact. With a triple you get that chain grinding if you try to go high-low or low-high because of the amount of travel the chain is making from side-to-side. As noted, it also doesn't require deraiullers being replaced.

mingsta

I think triples look butt ugly, so if I needed a larger gear range I'd go for a Compact, but thats just me being a tart.

But aesthetics aside, a compact is a much easier path for a double owner to go for. I have Ultegra 10 double, and if I decide to go compact in the summer for a Grand Fondo or mountainous Cyclosportif, I can just purchase the Shimano Compact and plug it straight in...probably won't even need to retune the gears if I'm lucky.

Having ridden MTB's with triples for a few years I also prefer the simplicity of just having two rings at the front. Maybe its just a coincidence but my Ultegra 10 setup has been the most trouble free gear setup that I've ever owned.

ggg300

https://www.bikeforums.net/road-cycling/123238-compact-crank-overload.html

DocRay

I know several who have had problems in Campy with switching to compact, they needed a different front DR. Some bikes have braze-on DR holders-they need to be removed. Some bikes with aero tubing-not an option.
FSA is spending a lot of money on marketing right now for compacts, because just being different can give you a market advantage, but really, there is a easier and cheaper way to tune gearing, and that is just change the rear cassette.

GuitarWizard

That's because Campy sucks

::runs and hides::

Grasschopper

This doesn't sound like a Campy issue but more of a frame design issue. I run a compact and Campy and it works just fine. I have a clamp on FD so I have nearly limitless adjustment in height of the FD. That said...sure some frames aren't (weren't) designed to have a brazeon FD and a compact crank...but that isn't the cranks fault...and the isn't a Campy issue...it is a frame design issue.

DocRay

Regardless, with a 53t front, I have the option to run as high as an 11t rear, or just change cassettes for lower gears. But a 50t compact, you are limited in your top gearing to 4.55:1, unless they can make a 10t rear.

roadfix

I think 4.55:1 is plenty enough for most......that's almost 123 inches......unless you want to descend at over 50 mph....

WheresWaldo

That thread never asks why, just tells you what it is and shows examples

WheresWaldo

Why wouldn't you always want to descend at over 50mph?