Recently purchased a Giant OCR 1 with triple crank. Now I am thinking that I should have bought a double due to the fact that I never use the smallest ring and I am assuming that having it negatively affects the chainline on the other two rings. What, how and how much? Thanks in advance.

Recently purchased a Giant OCR 1 with triple crank. Now I am thinking that I should have bought a double due to the fact that I never use the smallest ring and I am assuming that having it negatively affects the chainline on the other two rings. What, how and how much? Thanks in advance.

Triples work just fine. You never know when you might meet a hill that needs the granny gear. Changing to a double would require new shifters (assuming Shimano) as well as the crankset and bottom bracket. Might as well get a new bike if you don't like the triple. Leave it alone and enjoy riding it.

New shifters, crankset, BB, DR's, etc. I can see going from a double to triple as some people need the extra gears. But going the opposite? Why? It's good to have the extra gears when you need them, and if you never use them, so what? The chainline is specific to the gears you are using, and as long as you minimize large/small and small/large combos, you're golden.

Agree with fmw: enjoy your new bike and don't fret over this detail. An OCR-1 is great bike, and you should have plenty of excellent years riding it. And when you can afford that long overdue trip to the Tour de France and want to ride the Alps, you'll be glad you kept the third ring.

Recently purchased a Giant OCR 1 with triple crank. Now I am thinking that I should have bought a double due to the fact that I never use the smallest ring and I am assuming that having it negatively affects the chainline on the other two rings. What, how and how much? Thanks in advance.
What is your cassette? Consider getting one with closer gear ratios to provide a more constant cadence and to use the front rings. - TF

New shifters, crankset, BB, DR's, etc. I can see going from a double to triple as some people need the extra gears. But going the opposite? Why? It's good to have the extra gears when you need them, and if you never use them, so what? The chainline is specific to the gears you are using, and as long as you minimize large/small and small/large combos, you're golden.

Nonsense! Triple shifters will shift a double. All he needs is to ditch the granny and use a shorter spindle BB.Both derailers work with a double.

The middel ring is nearly as far right as the big ring on a double, so the middle ring and largest cog shouldn't be used, except briefly. The upside is that you can use the middle ring and the smallest cog. Whie you can get a double BB and take the little ring off, it does not provide a complete cure for the chainline problem.

If you have a 42 tooth middle ring, that creates a double problem, since the 42 with the next to largest cog is a 2-cog higher ratio than you would get with a 53/39 double in the 39 and largest cog.

I disagree that getting a closer ratio cassette is appropriate. If you reduce the size of the largest cog, it just makes the middle ring problem worse. With today's 10 speed cassettes there really isn't much difference in the jumps between the cogs, since all are straight blocks up to the 17T. 9 speed is different, with some lacking the 16T cog. To get the 16T you would need a 12-23 or 13-23 or 13-25.

Both derailers work with a double.

What then is the purpose of a short cage RD for doubles? Why do they make a short and long cage if, as you say, the long cage works so well with the double set up? Please tell me so that I can modify some bikes of friends who want to make the change.

And are you saying triple STI shifters work just the same with a double CR set up?

What then is the purpose of a short cage RD for doubles? Why do they make a short and long cage if, as you say, the long cage works so well with the double set up? Please tell me so that I can modify some bikes of friends who want to make the change.

And are you saying triple STI shifters work just the same with a double CR set up?
A short cage rear D looks more roadie and may save a few grams. Campy even has a medium cage so you can look just a little like you can't handle a 53/39-11/21. The long cage will handle anything and is the value RD unless the above matters.

Shimano-9 shifters, other than DA, will shift double or triple. Shimano-10 Ultegra and DA do not. I don't know about the 105-10. Double and triple front Ds are different and, though it may be good enough, I would not expect the same shifting if not using the correct one.

TF

Cranks & bottom bracket, front derailer @ minimum. The short cage rear derailer helps keep the the chain taught, while a long cage accomodates the chain slack necessary for the wide range in chainring teeth (30 - 52).

Keep the granny gear & just be sure that your cassette grannies out at 23 teeth or less. This is an ideal set up for anyone but racers. Ride if for a year first so that you can get used to it & know it, and if you by off chance can't find a comfortable cadence, consider a different combo.

As for chainline, save it for the fixies page. Modern indexed systems are designed to run with imperfect chainlines. Parts are guaranteed to wear out if you ride the damn thing, and unless you're on the the big cog in the rear & the big one in front, you've little to worry about.

Some will disagree, but few will be righter.