My ride came with a triple crankset. I think I've used the smallest ring twice in 4 years. Can it be changed to a double easily? Or, do I have to purchase a new crankset?

It would help if you posted the brand and model of your crank. Assuming that it's a typcal shimano triple, you could remove the little ring and install a new bottom bracket for a double crank. The chainline would still be about 2mm further to the right than it should be. Switching from a 118 to a 109.5mm spindle length will move the chainrings 4.25mm to the right. Most triples are about 6mm further to the right than a double.

A change to a double front derailleur would also be required if you want the shifting to work exactly like a double.

What are you trying to accomplish? I really don't see much penalty associated with triple cranksets.

If you want the look of a factory double set up, it'll take a new crankset, new bottom bracket and new front and rear derailleurs. The front shifting will be improved somewhat and you'll save between 30 and 150 grams.

It's possible to just take off your smallest chainring and dial in your front derailleur limit stop. You'll save around 30 grams but it won't improve anything.

What are you trying to accomplish? I really don't see much penalty associated with triple cranksets.

If you want the look of a factory double set up, it'll take a new crankset, new bottom bracket and new front and rear derailleurs. The front shifting will be improved somewhat and you'll save between 30 and 150 grams.

It's possible to just take off your smallest chainring and dial in your front derailleur limit stop. You'll save around 30 grams but it won't improve anything.
I'm looking at a new TT ring. I don't see many TT bikes with triples. I thought I would be able to remove the inner ring and re-adjust the derailleur limit. I just wasn't sure. My Ultegra triple works fine. I just don't really use it. I guess I can always leave it alone and replace the ring. keeping the "granny" for emergency use.

how is this going?. i too have a triple ultegra rig and I live in Florida! South Florida. Home of the flattest roads in the US with the exception of bridges over the waterways. I would like to convert to double, mainly bc I can't stand the look of triple anymore. I ordered by bike with a triple thinking i would take some road trips but that's not happening any time soon (new baby). My triple crank only has about 750 miles on it. How much would a legit conversion to double cost assuming I sell my triple goodies on ebay or something?

TIA

Switching from a 118 to a 109.5mm spindle length will move the chainrings 4.25mm to the right.

Why is this? If you have a shorter spindle, doesn't it move the crank and chainrings INWARD, therefore to the left?

Triples require longer spindles to accommodate all three rings without hitting the frame and to establish proper chainline. Doubles go with smaller spindles due to reduced clearance requirements.

So why does shortening the spindle move the chainrings out (rightward)? Is that a typo? Please don't have me draw another picture to prove it to myself C-40. My last drawing got, ummm, mixed reviews (although I thought it was darned good)????

You should re-read what C-40 said. "Assuming that it's a typcal shimano triple, . . . the chainline would still be about 2mm further to the right than it should be." This means that after removing the small ring and putting on a double BB, the triple crank's large ring would be 2 mm farther from the frame that would the large ring of a double crank. He never said that the ring would be farther to the right than a triple with a triple BB.

When I switched Ultegra triple to double, I got a brand new double crankset and bb off ebay (@$100) and installed it on my bike. Also got a new shortcage rear derailleur for about 35. Because I have two left thumbs when it comes to mechanics, I took it to an LBS for the adjustment. For about $150, I now have a double. Don't miss the triple, rarely used it anyway.

The mechanics dialed in the shifting with the existing triple front derailleur and it works fine (maybe a bit slow?), though I've also bought a double front derailleur for about $25. I just haven't installed it 'cause I'm gone too much to want to give it the LBS for a day. I mean, when I'm in town, I'd rather be riding than waiting for them to adjust the shifting.

I kept everything from the double set up. Cleaned it up and put it in a box in case I ever need it again.

how is this going?. i too have a triple ultegra rig and I live in Florida! South Florida. Home of the flattest roads in the US with the exception of bridges over the waterways. I would like to convert to double, mainly bc I can't stand the look of triple anymore. I ordered by bike with a triple thinking i would take some road trips but that's not happening any time soon (new baby). My triple crank only has about 750 miles on it. How much would a legit conversion to double cost assuming I sell my triple goodies on ebay or something?

TIA

Since you are concerned with "the look" you will need to replace the crank/chainring-set, both derailleurs, and bottom bracket. You will probably need to re-size the chain length.

You should re-read what C-40 said. "Assuming that it's a typcal shimano triple, . . . the chainline would still be about 2mm further to the right than it should be." This means that after removing the small ring and putting on a double BB, the triple crank's large ring would be 2 mm farther from the frame that would the large ring of a double crank. He never said that the ring would be farther to the right than a triple with a triple BB.

Since the triple large ring starts 6 mm RIGHT of the standard double large CR, moving it in 4.25mm to the left still leaves it 2 mm to the RIGHT of the standard double large CR.

he could get a 108mm BB which I have seen, although I don't know if it's Shimano compatible. It would move it in 1.25 mm closer than the 109.5mm BB does.

That's clearer. Thanks Kerry.

If you go from triple to a double, do you still use the same (I'm assuming STI) front shifter or doesn't that need to be swapped also?

the ultegra front shifters are double and triple compatible. No need to change it. the front DR is a different story if you want smooth shifting.

noob alert: is it my imagination of is the smaller ring considerably smaller than the second ring of a triple? if i just took of the granny ring would I be missing out on gearings i would otherwise have with buying a double? I'm trying to figure out what gearing would be best for flat Florida.

TIA, James