Record carbon front derailleur info

[Allan]

I bought this recently to upgrade from my 03 all metal Record one, since after a while rust eventually appears around the stamped holes in the back plate where the plating cant quite cover fully. I also wanted a lighter front derailleur that would be a better match to the new carbon crank as well.
I found that after fitting it up, the front portion of the cage was really close to the 53 chainrings teeth while there was a very huge gap at the rear of the 53 chainring, a quick glance back at the old derailleur and it was easy to see why the new carbon one had this big difference.
The carbon outer cage is a bit too tall at its frontal portion by the plastic guide, and because of this there is a space of 2mm below the plastic guide, while the old metal one has the guide flush to the bottom. In case you are wondering, both plastic guides are the same and fit right up to the top of the outer cages.
To correct this issue i carefully used a Dremel moto tool to reshape the curve of the carbon cage so that i got it flush to the plastic guide at the front and then tapered it back off gradually,just like the arc on the older metal one.
Shifting is now much cleaner since the chain is fully on the guide when going to the small chain ring,whereas before it was twisting on an angle as the plastic guides lower area is tapered a bit.
One thing quickly apparant is that with this carbon unit its now possible to get the full sweep of the rear cluster without having to fine tune the derailleur (aka one click more out as you go past the 16 cog if not it rubs slightly scenario). This is not a technical job but you must have steady hands and patience, if not you will ruin the carbon cage easily. It might be best to use a highlighter to draw the new arced line on the cage before you reshape it.

[Sensis [Crawler]]

I also changed over to a carbon front derailleur early last year, but made no modifications and have no shifting problems at all.
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[Allan]

Eric,
I didnt mention this in my original post about the derailleur but in order to save a few dollars, i bought the new carbon unit in a braze on model since its cheaper than the clamp model, and the reason for this was that i was planning to use back my clamp on fitting part from my 03 Record derailleur.
Also putting the braze fitting part onto my used 03 derailleur would get it sold quicker, since there are more people using braze type fittings anyway.
This was when i noticed that the frontal portion of the cage cage would not pass the teeth because it was now too low,BUT the metal cage passed with exactly the specified 2 MMs. This would have meant i would now have to raise the clamp on the frame, but why??? since the dimensions of the derailleurs should be the same.
Also there was that huge gap at the back portion as well that concerned me along with the reasons i stated in my original posting. If yours works well for you i'm happy it does, and now mine works really well too with the improvements i made.

[Sensis [Crawler]]

My change was braze-on to braze-on, maybe that's the difference. Out of curiosity, when I get home from work tonight I am going to look at it and see if the 2mm spacing is constant, or if it changes towards the rear of the cage.

[Allan]

Eric the difference of the 2mms is seen easily under the area of the plastic guide where the carbon cage extends down that extra bit.
This is not the case on the metal version, the guide is flush with the cage edge and both guides sit at the top of both cages flush. This means that the carbon cage is that extra bit deeper, but not right through its full length. I started removing the 2 mms at the front portion arc and reduced the cut gradually back to nothing as i got about 50% down the cage towards the rear.
Even so with the modification the chain still has plenty of room above the cage but it now aligns better with the plastic guides surface than before. As far as i know the Campy part number for that clamp (mine is a 32 dia)has not changed for years, and the one i had from my 8 speed Record clamp on front derailleur is the same too. Actually my 8 speed Record unit from 98 is exactly the same as all the Record models up to the 03 version, the only difference is that the clip in plastic guide is not fitted, you could in effect buy the guide and convert your old 8 unit to a 10.