Said mechanic here. There are many better than me but it was my full time gig for 7 years so I've adjusted my share of FDs, and i don't think there is any adjusting to get this combination of FD/crank/bb to work well. I've been out of the game for a few years now so maybe i've just lost my touch!
I like the suggestions of trying a road double. The issue with this one is the relatively deep inner cage of the FD would pinch the chain between it and the big ring, below the teeth. The high position shown in matts photo is the only position i could get it work in at all, and even then you have to be incredibly ginger with it. I think a FD with a shallower inner cage will work better. If you took the high limit screw out far enough it would allow the FD to swing up enough to not pinch the chain, but then it threw it over the big ring. I knew the list members here would have a good suggestion on FD model/style! -Brian On Thursday, February 23, 2023 at 10:04:16 PM UTC-6 Jeffrey Arita wrote: > Matt, > > I just saw this thread. I had your exact same problem (compact double > crankset w/ 46-30 rings + front derailleur). When shifting from small to > big, it wouldn't or the chain would jump over onto the crankarm. I was > sure I installed the correct front derailleur. > > I examined the FD I installed and saw that it was my IRD *Alpina-d* for > triples (wrong one for this use-case). OLD EYES, I'm guessing. I dug out > my IRD *Sub-C *and, of course, all was right with the world - excellent > shifting with the compact crankset. The IRD Sub-C > <https://www.interlocracing.com/shop/732003-ird-sub-c-front-derailleur-v2-double-braze-on-6827#attr=> > > is just another potential solution for your crankset combo (unfortunately I > checked and it seems to be out of stock and is backordered at many > retailers). > > Good luck, > > Jeff > Claremont, CA > > > > On Thursday, February 23, 2023 at 7:27:42 PM UTC-8 mmille...@gmail.com > wrote: > >> Thanks all. When the FD was lowered, the chain could not climb up to the >> big ring. First thing he did was lower it. I tried it myself, when I first >> got the bike. >> >> I just ordered a cx70. If that doesn’t work, I’ll get new VBC or figure >> something out. >> >> Also figured out the brake levers were long pull. So that explains part >> of the braking issue. Brakes are overrated! Ha. >> >> Matt >> >> Sent from my iPhone >> >> On Feb 23, 2023, at 9:16 PM, Joe Bernard <joer...@gmail.com> wrote: >> >> The hiccup here is his double is really more of a triple with the middle >> ring removed; lifting a chain from 28t to 46 is a big climb. I'm not sure a >> double is going to cover this, but I agree lowering the derailer is a good >> idea. >> >> >> >> On Thursday, February 23, 2023 at 5:52:25 PM UTC-8 Nick Payne wrote: >> >>> Your FD needs to be lowered a fair bit. At the point of closest >>> approach, there should be only about 2mm clearance between the top of the >>> chainring teeth and the outside derailleur cage as it passes over the >>> teeth. I have doubts about the experience of your "experience" mechanic if >>> he positioned the FD where your photo shows it. Making that change will >>> mean that the cage won't have to move so far outboard to get the chain onto >>> the big ring. And if you're only using two chainrings, fitting an FD >>> intended for a double rather than a triple would also improve things. The >>> sculpting of the cage on a triple FD is intended for use with chainrings >>> where there is a reasonably large jump in the number of teeth between the >>> granny and middle chainrings, and a considerably smaller jump between the >>> middle and outer chainrings. >>> >>> Nick Payne >>> >> -- >> You received this message because you are subscribed to a topic in the >> Google Groups "RBW Owners Bunch" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/rbw-owners-bunch/Zg1lQo3p8cY/unsubscribe >> . >> To unsubscribe from this group and all its topics, send an email to >> rbw-owners-bun...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/rbw-owners-bunch/10fb423e-0cbc-4088-a95f-df59b61ceec5n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/rbw-owners-bunch/10fb423e-0cbc-4088-a95f-df59b61ceec5n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> -- 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/e6a9b6c2-e59b-4c54-bf0e-651cd7a8771en%40googlegroups.com.
