Road Cycling - Difference between 2 and 3 Chainrings

I have always wondered why someone would get 2 chainrings over 3. It doesnt save too much weight and the smaller chainring can only make things easier. Anyone know why?
byron

cuz it makes you look macho! ;)

to be more of a badass on the tough climbs.

Actually, I don't know for sure. For me, triples weren't out in '98 in higher end groups, so it's just what I've got. I would imagine that the weight weenies out there don't like the extra weight of a chainring that doesn't get used all that often. If I lived in the mountains, though, I'd definately run a triple. The climbs here aren't over 2 miles and are all 6% or less, so it's not been a problem. I just can't justify the cost yet.

In addition to looking more macho
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Two-ring setup weighs less than three
Short throw derailleur hanger shifts quicker
Lower Q factor
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It really depends on your strength, weight, where you ride, and personal preference. It's sort of like the half-empy/half-full glass thing, to me. If you go for the triple, but only need it occasionally, you pay the cost of the functionality all the time, whether you're using it or not. On the other hand, the weight and shifting performance aren't killers 90% of the time... why hurt yourself on the climbs?

I recently bought a Trek 5200 with triple chain rings. I really do not need them as I live in Florida where the closest thing to a hill is going over a bridge. The reason that I got the triple is twofold. One because it gave me a larger middle ring. 42 tooth versus 39. Two because I had read in reviews that the 5200 (and possibly other models/makes) had a tendency to ghost shift into a non existent small ring when using a double set-up. Rather than risk frame damage I figured that all things being equal I had nothing to lose from getting a triple.

I actually can notice the shift speed in a triple vs a double. I had to decide between the triple or the double when buying my lemond, and I rode the triple first. the shifting felt good (105) but then I went to the double, and the shifts were quicker! I hadn't realized that the difference between the two was that much.

You can get a double with a 42/53 on it.

I cannot think of any climbs I would need anything small than a 39/25 on. I rarely use anything smaller than 39/21, and if I do, it would be a long climb over 10%.

For riders that need a little extra gear, it is a good idea.

Real men only use the big ring ;)

Oh, and another thing is that racers like doubles, because often when racing, you want to not have to think about chainline and finding the correct ring in the front. It is easier to just go big ring or little ring, and not have to search for the correct ring. Also, the difference between the small and middle is often quite large, and it often not a smooth shift, and in a race, you don't want a balky shift.

I have come to love on the 18% hills with my 24/36/44 x 11-34 (9) set. I won't even take my bike equipped with 42/52 x 11-24 (7) out if I know there are long steep hills.

I love the triple for good climbs. But in the flats, it is useless.

Originally posted by B1105
I have always wondered why someone would get 2 chainrings over 3.

Well, that's the way my bike came when I bought it. I bought a 2001 Univega at the end of last summer at a good deal. The LBS had 3 of them in stock, all with 2 chainrings. I originally wanted 3 chainrings, but this bike fit me so well... The bike has Campy Daytona 10 speed which would have been more trouble than it would be worth change it.

So, I figured I could handle the 2 just fine. So far so good, but the hills around here aren't too horrible (with a few exceptions). :)

Thanks for the replies guys!

Originally posted by georgesnatcher
I recently bought a Trek 5200 with triple chain rings. I really do not need them as I live in Florida where the closest thing to a hill is going over a bridge. The reason that I got the triple is twofold. One because it gave me a larger middle ring. 42 tooth versus 39. Two because I had read in reviews that the 5200 (and possibly other models/makes) had a tendency to ghost shift into a non existent small ring when using a double set-up. Rather than risk frame damage I figured that all things being equal I had nothing to lose from getting a triple.

I'm not sure why a properly tuned front derailleur would ghost shift. If you get the stops set right, you shouldn't have this problem. Is the frame flexy? And I second the notion that it's pretty easy to get a 42 tooth small ring on a two ring setup.

I'm really curious about this ghost shifting problem. It really seems like anyone that can work on a bike should be able to fix it (ie, your LBS or yourself if you spin your own wrenches).