Double vs. Compact Double

[Mags...]

I swapped my double for a compact double, and I did it myself. This was pretty straight-forward with my bike as I went from Shimano Dura-Ace double to Shimano compact double. It's all in one piece, the bottom bracket, the right crank and the 2 rings which are 50/34. When the crankset/BB is inserted through the hole in the bottom of the frame, the left crank is then bolted on the left side of the BB.

I didn't have to change any shifters, chain, or derailleurs. The FD was positioned a little too high for the compact, as the original double was sized 39/53, so this was shifted down a little bit - easy. I did have to spend some time fiddling/tuning the gearing into the FD as there was a little rubbing of the chain initially.

You should figure out what sort of cycling you'd like to be doing and there are charts/figures/sums you can do to work out what gearing ratios you'll get between one set-up to another. The range of gearing you get depends on what rear cassette you team the crankset with, for eg. 11/23, 12/25, 12/27. I've got the 12/25 and I've found that in comparison to what I originally had, which was the double 39/53 teamed with the 11/23 cassette, I've got equivalent of 3 lower gears for going up hills than I originally had, and have lost 1 gear at the top end. Seeing as I'd never used that one anyway, it was no problem. I use the larger front chain ring more often now. It takes a little getting used to but I'm happer with the changes.

[bike4ever]

We also put a compact double on for a customer without changing the front derailleur. I put a compact double on my Lemond this season and needed to change the front derailleur since I am using Campy. We just couldn't get the standard derailleur to work. My crankset is Bontrager Race Lite so I didn't need to change out the b/b.

[velogirl]

We also put a compact double on for a customer without changing the front derailleur. I put a compact double on my Lemond this season and needed to change the front derailleur since I am using Campy. We just couldn't get the standard derailleur to work. My crankset is Bontrager Race Lite so I didn't need to change out the b/b.

I'm a campy girl, too, and I've been running a compact double since they first came out in 2003. I didn't change my front derailleur since there weren't compact-specific FDs available at that time. And I've never had problems with the standard FD.

[alpinerabbit]

Yep, swapped to a compact double, with a new cassette thrown in (larger Granny gear) - no change to the derailleurs required.

[bike4ever]

velogirl - I'm glad your campy compact worked out well. We tried everything we could to try and get it to work. I believe it has to do with the Bontrager crankset paired with the Campy front derailleur.

[DebW]

Nothing new to say, but I'll say it in different words. Every crankset has a minimum sized chainring it can take because of the size of it's spider arms and the diameter of it's bolt circle (the bolts that hold the chainrings to the arms). You need to find out the brand/model of crankset and it's bolt circle diameter. Then you can find out what the smallest chainring it can take is (probably 39). A compact double is made to take smaller rings (probably 34) than a standard double. Your Waterford may come with a 42 inner, and if so you could go down to 39 for minimal expense. Increasing the cassette size very much will most likely require a new rear derailleur (looks like a short cage in the pic), but going to a compact crankset probably will also.

[KnottedYet]

Thanks you guys!

Gee, the amount of knowlege on TE is just so cool. You guys are great!