Originally Posted by
redxj
It depends on the triple. Common triples are five arm 130/74mm or 110/74mm rings. Compact doubles use 110mm rings. If you have a 110/74 ditch the granny gear and add some suitable 110mm chainrings for a compact double. I have done this in the past with some of my own bikes using mtn triples since they are often 175mm in length and I am tall. If you did want to go with a futuristic outboard bearing compact double the SRAM S350 is nice at $100-120 with BB cups. I am running a compact Rival crankset switched to 48/34 rings on my rando bike. I am also a fan of going even lower with the compact double, 46/30t instead of 50/34. But, that can't be done on a 110mm BCD crank unless the granny is used as the 30. I have a TA Cyclotouriste crank that is getting 46/30t rings and an older Sugino XD (older 94mm BCD) that is setup as a 46/30.
man, does everyone have a TA crankset? I am so jealous. if VO weren't out of their TA copies (and if they weren't around $200) I'd totally get one of those beauties.
anyways, I do have 110 on that triple. will probably dig around the co-op for some old MTB rings in the compact range. for a fairly large rear cassette (11-32) does 48/34 sound reasonable?