Campagnolo users: front derailleur with 46/30 subcompact chainrings?

slowpoke · #1 03-08-2021, 09:02 PM

Question for the Campy 11-speed riders: can you use the stock Athena/Potenza/Chorus/Record front derailleur for 46/30 subcompact rings, or did you end up swapping it out for the ubiquitous Shimano FD-CX70?

Thanks!

bikerboy337 · #2 03-08-2021, 09:08 PM

Sorry if this isn't much help, but I'm running campy shifters/RD on my TI warbird, but it requires top pull FD, so I'm using the Shimano CX70, and it works perfect... if campy made a top pull FD, i'd be all over it, but... hey, it works... sort of a frankenbike with FSA cranks, Campy shifters, RD, Paul Klamper brakes, etc...

In any event, i find the CX70 works great for my needs with either a 48/32 or 46/30 crank, i've run both on this bike...

slowpoke · #3 03-08-2021, 09:14 PM

Yeah, I've read that the cage of the Shimano CX-70 has a tighter arc because it was designed for a max 46t ring.

I'm wondering if shifting will not be as good with the regular derailleurs because of this.

R3awak3n · #4 03-08-2021, 09:40 PM

I have ran 46/30 with campy front derailleurs and always have worked fine, actually just setup s bike with exact setup. Athena front shifting a 46/30 and athena rear shifting a 11-34. All things that were never even thought or approved by campy

jtakeda · #5 03-08-2021, 10:22 PM

I’m doing 46/30 WI crank with a chorus 11 FD AND a 73mm shell and shifting is dandy. 11-34 cassette

You’ll be fine

oliver1850 · #6 03-09-2021, 12:48 AM

I would think the Athena 11 triple FD might be the best option, but not sure about function with various model years of double shifters.

https://www.campagnolo.com/media/fil...gnolo_2016.pdf

robertbb · #7 03-09-2021, 04:53 AM

This is interesting.. there's a Shimano FD that is known to work with 46/30 cranks and Campy shifters?

Shimano FD-CX70

What's the diff between top pull and bottom pull?

Very interested in running a sub-compact.

oldpotatoe · #8 03-09-2021, 07:00 AM

Quote:

Originally Posted by slowpoke

Question for the Campy 11-speed riders: can you use the stock Athena/Potenza/Chorus/Record front derailleur for 46/30 subcompact rings, or did you end up swapping it out for the ubiquitous Shimano FD-CX70?

Thanks!

Depends on LH shifter. If 11s and UltraShift..early 11s(2009/10) anything or SR/Record/Chorus..Either the standard Campag front der or the CX-70..either will work.

The only caveat is if it's clamp on and the seat tube is kinda steep, the 'tail' of the fder 'might' be a little high..and the 'bump' on the front der that brings the chain from the small to big ring 'may' be a little high to shift reliably.

LeMond123 · #9 03-09-2021, 07:08 AM

I wouldn't bet on the triple getting good shifting. I thought a 46/30 might work on a Shimano bike with a triple, but that triple (and I imagine the Campagnolo) has like a middle "channel" that only works well for about 10-11 teeth less than the big ring. It's wide in that area for no rubbing across many gears, and skinnier above and below. The triple rubbed like crazy, and shifted terrible on the stand. When I switched from my old triple FD to the CX-70 on that bike, shifting was great (this was again, using Shimano shifters), even on STI. Anecdotal evidence indicated that a standard cage (especially older models) would work well with friction and/or the Ergos with +/- 12 clicks or so which offer so much flexibility. YMMV - good luck!

Elefantino · #10 03-09-2021, 09:05 AM

11-speed Chorus front with FSA SL-K 46/30. Works just fine.

thwart · #11 03-09-2021, 10:12 AM

Data point, although of course, YMMV.

Got tired of cleaning up the FD pulley on my winter/gravel bike, which is an older cyclocross Moots frame with traditional top tube derailleur cable routing. Has a Praxis 48/32 crank.

Tried the top pull Shimano CX-70... yeah, it works, but requires more attention/trimming than the 10 spd Campy bottom pull FD I was using before, with the pulley. Appears the cage width/geometry is different enough to matter. This may not be the case for you...

Then I tried the Umlenker thingie (to run bottom pull FD's w/o a pulley)... it didn't work well at all.

So I'm circling back to the pulley and bottom pull (Campy) FD.

slowpoke · #12 03-09-2021, 06:10 PM

Quote:

Originally Posted by robertbb

What's the diff between top pull and bottom pull?

Where is the cable being pulled from? If your derailleur routing is along the top tube (traditionally for cross bikes to minimize mud contamination), you'll need a top pull derailleur or use a pulley as thwart mentioned to re-route the pull.

- - -

Thanks for all the anecdotes everyone! Seems like page 3 of this tech manual says 46t rings are supported: https://www.campagnolo.com/media/fil...ev04_08_17.pdf

robertbb · #13 03-09-2021, 07:16 PM

Ahh, got it. Thanks for that! Never had a bike that had FD cable routed in any way other than "up" from the bottom bracket.

mistermo · #14 03-10-2021, 01:16 PM

IRD Alpina front derailleurs are known (designed?) to work with smaller rings.

cgolvin · #15 03-10-2021, 02:22 PM

Yet Another Solitary Data Point.

TL;DR: yes, it works

I've been running an Athena 11 FD on a PlanetX with TT routing and a disc/pulley to accommodate the bottom pull (Chorus 11 RD, not that it's relevant), previously on a Red 50/34 crankset but recently switched to a GRX 46/30. Campy bar end shifters.

It took a lot of force to move the chain to the big ring, irrespective of chainrings/cranks, and on the first ride with the GRX the left shifter broke. In replacing it I changed the cable routing (emerges at the bend of the bars rather than near the stem), replaced the housing inner running down the ST portion with a piece of full housing, cleaned and greased the disc/pulley. Now the shifting is more normal.