To prevent article pages from being miles long, but preserve all the useful questions and answers provided over time, I've decided to copy/paste the website comments to the forum - and "move" further discussions here.
These are the comments from the article:
Compatibility  Front derailleurs
These are the comments from the article:
Compatibility  Front derailleurs
07/06/2017 at 18:55
Excellent information – thank you. Have been hunting the internet for answers on FD angle of inclination / curve to match front chain ring – and at last found the answer I needed .
06/11/2019 at 20:29
Thanks!! Do you think a Shimano Sora R3000 FD will work with 36/22 or 38/24 chanrings? The FD limit is 46T
06/11/2019 at 20:39
It won’t work brilliantly, since the larger chainring is a lot smaller than what the FD is designed for.
The fact that smaller chainring is also smaller than anything one would generally expect on a road double (34 is general, while 30 is the absolute minimal) certainly doesn’t help.
Having said that, depending on one’s criteria of “good” (or “good enough”), it can be OK. Especially if (front) shifting under load is avoided (though that’s generally always advisory, but in this case even more so).
19/02/2020 at 18:18
Thank you very much
This is very informative and has everything i needed to know!
26/03/2020 at 15:15
Hi, I have Shimano Tiagra 4700 2×10 shifters and I need to use a top pull FD, but for road doesn’t exist…I see the Salsa fargo is using tiagra shifters and deore fd-m6025…is it correct?
26/03/2020 at 17:14
Then If I will use any 2x shimano FD with tiagra 4700 road, playing with the screws It will work..not perfectly but works..isn’t?
Even if the FD is a dyn-sis technology?
27/03/2020 at 05:31
It depends on your criteria. In my experience, for 2x, almost anything can be made to work OK. Not perfectly, as good as it possibly can – in terms of fast shifting, especially if attempted under (slight) load, but OK.
However, I haven’t tried every possible combo, so can’t bet my life on it, sorry.
Either way, do let us know what combo you end up making and how well it works.
- Chris Woodward
31/03/2020 at 16:58
Hi, Hope you can help. I have bought a Calibre Stitch hybrid bike which i like, apart from the chain rubbing the front derailleur Claris) in a few gears when the chain is over angled. I have a spare front Altus, which has a wider gate. Do you think this would be compatible, and solve the rubbing problem?
31/03/2020 at 18:53
If all is properly adjusted, having the chain rub when “severely cross chained” (as in – using the largest 2-3 rear sprockets from the largest front chainring and/or using the smallest 2-3 rear sprockets from the smallest front chainring) is a nice, harmless warning that your choice of gearing is not very good for the chain.
I suppose that going with a wider cage FD can help eliminate that, or at least make it audible only for the very extreme combos (like the last 1 rear sprocket at the opposite side from the used front chainring, not 2-3 sprockets).
Altus is not a perfect match for the Claris shifters, but it could be made to work satisfactory (depending on one’s criteria), especially with double front chainrings (with 3x it’s a bit more of a hassle). But it would be solving a problem that doesn’t really exist. Like using poor brakes, because a bicycle goes hardly when brakes are applied (sorry, can’t think of a better example).
01/04/2020 at 10:19
Thanks for that. I think i will just live with it, and take note when its rubbing, and change to a more appropriate gear.
04/04/2020 at 10:47
Hi, Maybe you can help me out.
It seems there is too little information around yet about 12 speed stuff. However, I’m trying to hack together a 2X12 system for a 29+ Drop bar frame for extended off-road touring (probably using 2.5”- 3.0”). I’m a Campagnolo user and have worked out everything except for the front derailleur / chainring combinations. I’m thinking I’d like somewhere from 19-120 gear inches. Jtek make a shift mate for Campy 12 – Shimano MTN 12. So with the Shimano 12s 10-45 rear cassette I’d need a 42-28 or 40-30 chainring or thereabouts (boost spaced 104-64 spider on Race Face cranks). This leaves me with a quandary. How do I get a derailleur to work with a 12 speed Campagnolo shifter over teeth that are that size? The smallest chainrings that Campagnolo suggests for the Chorus front derailleur are 48-32. Could this derailleur be modified to work? (Angled shims, Band on adapter for boost spacing). Would the Shimano 2X12 derailleur work better even though it’s specced for 36-26 chainrings. Is the pull of the Campagnolo 12 shifter going to be able to move the derailleur into the right position? I’m so lost.
Thanks for the write up btw. I learnt more about the front derailleur from this post than all the previous things I’ve ever read.
04/04/2020 at 11:15
I’m afraid that I can hardly say anything you don’t already know – sorry. But won’t waste too much of your time (the reply is still under 10 pages long ).
Firstly I have to make a disclaimer: I live and work in Serbia, a rather poor, devastated country, so don’t see much of the new stuff – until it becomes the old stuff.
My estimates from charts, specifications and manufacturer inquiries are usually correct, but think it’s fair to point out for stuff that I haven’t personally tested.
To make things even worse, Campagnolo is like a unicorn here: everyone knows it’s nice and cool, but no one’s actually seen it!
OK, being a mechanic, I get to see a few – more than the “normal” cyslists (if there is such a thing ), but still not very much.
Secondly, I’d give myself the liberty to add, even if not asked, that for touring I’d go with simpler, more robust stuff – like friction shifters and fewer cogs at the back.
Using triple front chainrings.
This easily provides wide enough gearing ratio, with gears still being “tight” enough so that the desired gear ratio is always available.
Another advantage of such systems is they work flawlessly with practically any chain (or cassette for that matter) that you throw at them (this can matter in case of a malfunction while away from any well equipped store).
OK, with all that out of the way:
I would expect 42-30 to work OK with a derailleur for 48-32. If fast shifting under load is not needed (like when racing), and if one’s criteria of fast/smooth front shifting is not too strict, it would probably work OK. I’ve mix-matched road 50/53 large chainring double FDs with MTB cranks and had them do just fine – especially with the doubles.
For mixing Shimano FD with Campagnolo shifter – I haven’t tried that, so will have to look up the manufacturer specs (if there are any cable pull specs) and see. I would bet a beer that it can be made to work, with a double, but can’t say for certain, unfortunately.
22/04/2020 at 14:56
Thanks for great content on the site! I have a bit of conundrum with my front mech setup, hoping you would be able to help maybe?
I’m looking to build a CX bike around an old frame which is equipped for a top pull cable routing. I find it extremely hard to find a fitting FD
– CX70 (top pull) seems to be good candidate, but it proves extremely hard to get (at least based on my attempts so far – either out of stock, or even when sellers claim they have this, in the end they delay and decline the order…) and then also I’m worried about compatibility – would it work with Tiagra 4700 shifter? (Shimano claims compatibility with 10 speed groupsets, but apparently 4700 has different pull ratio than previous ones…)
– secondly, Ultegra FD-8000 claims to be “Dual Pull” which would mean both bottom and top; 105 and GRX seem to share the construction and also claim “more cable routing options” but any setup instructions only show the bottom pull setup – so how is that in real life?
– finally another option would be to engage some MTB derailleur which more commonly come in top pull, but then again would that work OK with road shifters (Tiagra 4700 or 105 7000 series)?
Thanks in advance for any insights on this!
22/04/2020 at 18:40
Shimano’s compatibility charts are given on their website and are usually quite conservative – meaning that whatever they say will work, works.
4700 front shifter (as well as their 11 speed road shifters) pulls more cable than the other Shimano’s front shifters. For doubles, FD limit screws can help so one can make it work OK (depending on one’s criteria of how good it has to be for it to be considered “OK”).
Stated “more cable options” means that the FD accepts both the “naked” cable, and the cable that comes with housing, all the way to the FD (the FD has a housing stop built in). However, for all I know, in order for that FD-8000 to accept top routed cables, one would need to use an adapter.
Hope this helps, let me know if you have more questions.
25/05/2020 at 06:04
Just wanted to know if the old 105 fd(5800) is compatible with the new 105 crankset (r7000)?
Thank you in advance!!