Modern triple FDs are designed for a specific combination of chainrings. For example, the IRD FD in the photo is an exact copy of the Shimano 9 speed Ultegra Triple and 105 Triple FDs. Probably made by the same company that made it for Shimano. The bottom edges of the derailleur plates are properly spaced for the 10 tooth difference between the outer and middle chainrings of the Ultegra and 105 9 speed triple cranksets; 52 and 42 teeth respectively. When properly installed, the bottom edges of the derailleur will be about 1mm to 2mm above the tips of the chainring teeth when shifting between the outer and middle rings. So this FD only shifts well if the middle and outer rings have a 10 tooth difference. If, for example, they have a 12 tooth difference, and you have the FD high enough for the outer plate to clear the outer chainring, the inner plate will have a larger gap to the middle ring and the shift from the inner ring will not be good. With a 14 tooth difference, it's hopeless. You'll have to over-shift to get the chain cleanly onto the middle chainring.
So, to answer the original question, we need to know what chainring sizes are on the crankset in question. On Sun, Mar 26, 2023 at 1:04 PM Matthew Williams < matthewwilliamsdes...@gmail.com> wrote: > Hi everyone, > > I need to replace my stock Rivendell front derailleur. Can someone please > recommend a good front derailleur? > > Here’s my existing setup: > > Appaloosa > Rivendell Silver crankset and 3 rings > Rear cassette: Shimano XTR 11-34T > Rear derailleur: Shimano Deore long cage > > With the exception of the rear cassette, all of the components came stock > with the bike. > > I picked up a Shimano Altus FD-M311 at the swap meet. Will this work for > my setup? Does a better option exist? Please let me know your > recommendations, advice, opinions, and experience! > > Thanks, everyone. > On Thursday, February 23, 2023 at 9:45:08 AM UTC-8 mmille...@gmail.com > wrote: > >> I've been having a heckuva time getting my front derailleur to go from >> little to big without hopping over. Eventually, if I talked sweetly to it >> and said Hail Mary three times, it would usually settle. Even took it to an >> experience mechanic. He also lowered it, then slowly kept raising it up, >> and also kept working the limit screw. A fraction of a turn was difference >> between not reaching the big ring, or going over! >> >> It's a White Industries VBC with 46-28. FD is IRD compact triple Aplina. >> Friction Microshift thumbie. I think it's bottom pull. >> >> [image: IMG_2391 Medium.jpeg] >> >> Any suggestions for different FD? May need different chain rings because >> of that big jump, but if I do that, I may be best off buying something else >> and selling these. >> >> Thanks, >> Matt >> > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rbw-owners-bunch+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/rbw-owners-bunch/68001ed0-b4c8-4dee-b847-7eea267cf44fn%40googlegroups.com > <https://groups.google.com/d/msgid/rbw-owners-bunch/68001ed0-b4c8-4dee-b847-7eea267cf44fn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- Peter White -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/CA%2BD%3DXm9xvzcaCz%3DjyPubTzGZORaWUiEaq4D7pTNtFNSWYjxnKg%40mail.gmail.com.
