I am toying with the idea of making my double into a triple. What do I need to accomplish this?

I have 10 speed shimano STI with 12-27 ultegra cassette and 50/36 Truvativ crank.
Short cage ultegra derailler and a 10 speed Shimano 105 chain.

From what I can gather, I need the triple crank(duh), long cage RD, and a triple compatible left brifter. But it looks like it is going to cost at least $500 for the whole kit and kaboodle!

If you feel the need to go triple because you have trouble climbing and you never use the 50+12 combo, then you can drop the 36 ring for the 34 ring for cheap.

As for going triple, you might have to do something with the bb spindle length to make sure the chain line is good and the rings don't damage your stays, though I'm not 100% sure.

You will need a front dérailleur. You might be able to get by with the short cage rear dérailleur, but I wouldn't bet on it.

Another option is using 9-speed components (STI, CS, BB, FD). Much cheaper.


That's all taken care of with the integral spindle on 10-speed crank.

Good to know - I found that out when working on a singlespeed with a square bb so I wasn't sure.

36 gear inches vs. 30 gear inches for $500.00. That's $83.33 per gear inch.

A 34 tooth ring for your compact crank might only cost $18.00 to $25.00. That'll only give you a hillclimb gear that's a couple of inches lower but it'll only cost you $9.00 to $12.50 per gear inch.

I just changed my double to a triple. Here's what I changed out.

Crankset of course. I'm running a 53/42/28
Front Derailleur. Picked up a Campy Record triple FD (new) very cheap off EBay.
Rear Deraileur. Picked up a Campy Chorus Long Cage (new) RD cheap off EBay. I needed this because I had a short cage RD and had changed out my cassette from a 13/26 to a 13/29.
Chain. Needed a little longer one.
I was using Campy Record shifters, so that was no problem. Might be for you depending if you have the 105 shifters or not. I've heard 105's work good for either triple or double.

Edit: Opps.. Sorry forgot something. I had to change out the bottom bracket as well. I had a 70x109 and switched to a 70x118.

I've loved having the triple. I only use the triple in the mountains and I still have pretty much the same gearing I had with the double. Working great for me.

Good point, I think I will try out the 34 and see how that goes. From what i can tell, the only place that sells a 34 with a 110 BCD is Harris cyclery. Right?