FD w/Compact Cranks?
 

For those of you have or have had compact cranks did you use a regular double FD or one of the "compact specific" FD's? I have the Centaur CT cranks, 50/34 and a 12/25 cassette, if this even makes a difference. I have heard people say it will work by lowering the regular FD and I have heard people say that it won't? :fight: So is there a general consensus out there as to the route of choice? Thanks for any input!

I use a regular road double FD. I believe the spec for a Shimano is big ring 50-56 and max difference of 15T.

The new Shimano 10-speed 105 FD actually has a max total of 16t (for the double). I don't know if that's a typo or what not, but that's what it says on Shimano's website.

I am currently using a regular FD with my Campy Centaur compact crank. It's okay, but I have to be ginger when shifting between the 50/34 chainrings. I have the derailleur as low as it needs to be, about 1mm from the teeth of the 50 chainring.

I will probably get a compact specific derailleur soon. Right now, I simply can't shift between chainrings and hammer away else the chain skips around pretty badly.

I just converted my triple (Record crankset, Chorus FD and BB) to a Compact (FSA SL-K MegaExo). So far my Chorus Triple FD works fine.
I had to lower the FD to make sure clearance above the 50 ring is as recommended, that's about it.

Anyone here know how to lower a brazed-on mounted FD?

Very carefully dremel or drill the slot a little longer/lower.

I ran a regular FD with the FSA Mega Exo SLK 50/34 crankset. I never had any FD shifting problems. I lowered the FD about 5mm and made small adjustments to the shifter cable and limit screws. Personally, I don't believe you need a compact specific FD, but then that opinion is based on my experience with this set up.

Obvious solution....I didn't even think about doing that! ..:)
Would I be able to bite into titanium?

That's a question for someone that knows what they're doing :D

Here are the specs for the Veloce FD from the Campy site, for classic Ergopower™ shifters - for double standard crankset - capacity 15 – max. chainring 54 - min. chainring 39, should this be any reason for concern? Maybe I am just having buyers remorse for no apparent reason, yet.

When I put a Ritchey WCS compact crank on my Flite 2000 (braze on FD) I went to a IRD compact dérailleur to avoid having to modify the braze on. It works perfectly. Lots of members seem to have good luck with regular dérailleurs on their bikes, so it doesn't seem to be a hard and fast rule, but I've never had to look back by switching it out up front.

I had some intial problems with my cannondale compact, SI crank is made by FSA, on my six 13 it was throwing the chain over the 36 ring and derailing the drivetrain. LBS thought a compact derailer the FSA c16 or one by IRD would solve the problem. but having done some research on the net I found that the FSA rings are machined a little bit wider.This causes a problem with the ultegra and 105 10 speed chains the added friction to move the chain off the 50 ring builds up and then it suddenly throws it over the 36 ring. Putting a Dura ace chain on solves this problem because they use a 9 speed roller and narrower plate to maintain the narrow chain width 6.1 mm and the wider chain rollers don't hesitate on the downshift. I use a standard ultegra FD and it shifts great now. the shimano CN 7801 new model DA chain is very smooth. LBS was still going to change the FD to a compact one but I said don't it shifts really well now . compact cranks are awesome.

I use a Chorus starndard FD with my FSA FSK 50/36 11/23 set up and it shifts flawlessly. Zinn recently said that the Campy compact setup will only work with a Campy CT FD.

http://www.velonews.com/tech/report/...es/9391.0.html

I run Stronglight Pulsions in 48/34 and I use a Record Compact FD (band on) - works well. However I understand the received wisdom is that for Campagnolo compact cranks - use a compact FD, and for non-Campagnolo compact cranks - use a standard double FD.

Well with you only having a 14 tooth difference it should be fine, according to Campy's 15 tooth difference. From what I gathered from that article though was that the Campy CT FD could only be used with the Campy compact cranks, not necessarily that you had to use the CT FD with the cranks though. That was just how I read it anyway. Thanks for the input!

I've got the regular Ultegra FD.

Did the IRD derailler hang lower to the chain ring or does it just have a different contour on the cage?

FWIW I use the same set up with a 36t inner ring.

I have a 34/50 Centaur with a standard Veloce FD. I don't notice any difference from my old standard crankset. The bikeshop set it up for me though, I think all they did was lower the FD a bit.

I have two bikes with compacts on them both...FSA. One bike uses a reg and the other has a spc FD. Both shift fine...for the reg just lower the FD a bit. Most FD are cheap so do not stress too much...for more reading...post number 4:

http://www.bikeforums.net/showthread.php?t=123238

ask rad/55 as he had some issues like this...http://www.bikeforums.net/showthread...=compact+crank

for more reading...http://www.bikeforums.net/showthread.php?t=123238

Wow....thanks for the links! I remember those threads and I will go through them once again this evening. Interesting to read (again) what sydney had to say in all this....:)

Thanks thad! You hit the nail on the head, for my situation at least. This will be the same set up I am running. Did you ever get your Orbea that I lead you to on eBay?

Your 1st post said you used a 50-36, which is a 14 tooth difference, which is within Campy's range of 15. Did you mean you use it with a 34 inner? Either way thanks for the help/info.