Road Cycling - Front derailleur for compact drive crank set

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Sierra
08-30-04, 10:14 AM
I'm building up a bike that I plan to equip with a 34/50 compact drive crank set. I'm wondering if I should get a front derailleur meant for a triple to shift this wide range, or if one for a more "normal" road double will handle it as well. Cassette will be a 12-27 9 speed if that makes any difference.

almarktool
08-30-04, 10:41 AM
i just did that combo and i a switched to a double shimano 105 front derailer
zensuit
08-30-04, 10:42 AM
I'm building up a bike that I plan to equip with a 34/50 compact drive crank set. I'm wondering if I should get a front derailleur meant for a triple to shift this wide range, or if one for a more "normal" road double will handle it as well. Cassette will be a 12-27 9 speed if that makes any difference.

Can you do any harm by getting a triple front der? If not, why not?

Steelrider
08-30-04, 10:52 AM
Hi Sierra,

I haven't gotten a compact yet (waiting - in vain so far - for Shimano..), but have looked into this and you can certainly use a double front. Only thing that has been mentioned to me is that you might have to lower placement of it. This could be problematic if you have braze-on vs. clamp. Clamp obviously no problem, but braze-on could force you into a triple - and more $. Hope this helps.

Man, you are going to be able to take on some hellacious hills with that setup!

Have a good one!
Sierra
08-30-04, 12:05 PM
Almarktool, thanks for your reply. Does your 105 double do an adequate job of making the shifts?

Steelrider, for me, this is just an acceptable level of gearing for handling hills. I set my wife's bike up with a 30/42/52 triple and Sheldon Brown's 14-34 cyclotourist 9 speed cassette. You can really handle the hellacious hills with that! I've heard too many stories of ruined knees from pushing gears that are too big. I hope to ride for a long time yet, and bad knees don't figure into that plan.
fogrider
08-30-04, 05:02 PM
Can you do any harm by getting a triple front der? If not, why not?

I set up my bike with a 48x34 compact crank with a standard double derailleur and it works fine. I did drop the mounting height a bit more, but my bike takes a clamp on. I think a triple might be a bit more sloppy. I use 11x25 cogs and this give me just the right spin for uphill and downhill.