SJX426 

Don't know if this should be in the C&V forum or not. Because it is a 10V FD I thought this is the right place.

I am mounting a braze on FD on my 1990 De Rosa. Come to find out it interferes with the 53t chain ring at the highest spot on the FD hanger. I was shocked. I thought all road FD's had about the same pivot point distance. Guess not. The FD on the Pinarello is fine with the location about the center of the hanger.
Problem


FD in question


The distance between the pivot points is very close to 23.5 mm


The Chorus 10V FD on the Pinarello is 18mm. About 5 mm shorter.

So what gives? Did Campagnolo make a FD specifically for compact doubles?

Do I have a FD for a triple crank set?

When looking for a replacement, how do I know what the pivot distances are? I don't what to buy every FD available and find the right one.

Litespud

there are clamp extenders (don’t know if I have the terminology right) that go in between the frame mount and the FD, allowing you to mount the FD lower beyond the limits of the frame mount for mounting smaller chainrings. Could they also allow the FD to be mounted higher? In saying that, though, I don’t know how old the FD is, but I took a quick look at my Chorus 10sp FD (early 2000’s) and the cage is clearly a different shape than yours (sorry about the crappy pic) - your inner plate is deeper and more “shaped“ than mine. Also, a quick'n'dirty pivot-to-pivot measurement on mine was ~16 mm. I didn’t know there was a Record-level triple drivetrain, but your FD looks like a triple.

nomadmax 

That looks like a 10 speed "compact" FD. Large chain ring is usually not bigger than 50T.

SJX426 

Self schooled since posting. What I have is a FD for triple crank set. Note the inner plate being so much further down than a double FD.

It doesn't work because the Big ring is too close to the center of the bike. In other words the FD is expecting the middle ring of the triple to be in this position with the outer ring further out. The FD moves up and out from the small ring position and it does not expect the middle ring to be 53t!
Sheldon states that the outer plate of the cage can be filed if there is interference. I am not willing to do that because of buying the wrong FD. Yet...…

Compensated on my build by installing a Superbe Pro FD until I can find the right FD at the right price.

Dave Mayer

OK: you've figured out that you have a triple FD. These are far less common and more valuable than the double versions, so if nothing you should be able to swap yours for 2 or more conventional double FDs.

Other variations: the CT front derailleur designed for the compact crankset. Typical chainrings in the CT crankset: 50 and 34, or my fav combo: 48/34. This derailleur sort of looks like a triple due to the deep drop of the inner plate, but it is designed for small double rings.

Then there is QS for Quickshift. Sometime during the 10-speed era, Campy changed their front shift cable pull, and redesigned the front derailleur with a longer arm that attaches to the cable. For a lighter action perhaps? You should match QS front shifters with QS front derailleurs.

In any case: the better Campy front shifters are micro ratcheting, so almost any road front derailleur will 'work', particularly with the standard 53/39 ring combo. So Shimano, SRAM, the later and better Suntour units, etc.

Drew Eckhardt 

Briefly, but that would have an alloy fork and plastic insert.

Yes.

A metal Chorus or Record double front derailleur will have an inner plate closer in side to the outer and plastic insert.

There was also a carbon fiber forked Record double front derailleur.

Drew Eckhardt 

For future reference.

Left to right: Racing-T 8 speed steel triple derailleur, Chorus 10 speed CT compact derailleur (note plastic insert at the outer front), Chorus 10 speed Standard + CT derailleur

Record 10 speed alloy triple derailleur. Note no insert.

SJX426 

Drew Eckhardt Thanks!

Road Fan

are they not making a compact front mech now?

Drew Eckhardt 

The dedicated CT compact derailleur lasted a few years at most.

Anecdotally people found the standard double derailleur worked well enough. Not surprisingly Campagnolo switched to a single design.