Michael, Good thoughts.
It's not actually at the limit of the set screw, rather, the set screw is in far enough that (ironically) it's quite difficult at times to shift into the big ring. At one point during my after-work ride yesterday, I was not able to get it to climb into the big ring at all. It was just grabbing at the ramps but not jumping up. Later I tried again and was able to shift into the big ring without incident. I tried to leave it in the big ring as much as possible which is more doable with the 11-34 I recently installed. I find that it's most likely to settle in under medium pedal pressure. Too light, and it doesn't climb at all, too heavy and it jumps right over. But anyway I will start from scratch as soon as I get some time, which may be after Saturday. I have appointments the next three nights and then the local RUSA group is doing an overnight 300K on Saturday night/Sunday morning so I am loath go to messing with my front derailer the afternoon before that. If re-doing the set screws from scratch doesn't help I will try angling the cage slightly, I'll come back and read the thread as to which way I am supposed to angle it at that time. I don't really relish the thought of bending the front derailer either, since it seems to work well for other people. However, if that is a viable option I'd probably rather pay someone else to do it that has successfully performed the modification before. As for chains, with my old rear derailer I was shortening chains two links out of the box when I installed them with the SRAM or KMC chains that I use as they come with 116 links. With this new one and the 11-34 I left them all on. The front shifting is about the same either way. I agree that nicer chainrings shift better in general, however, I had a TA Carmina crankset installed before this and it overshifted with about the same frequency. Granted, it did shift better when it wasn't overshifting. I could get shorter arms for the Carmina now that I have converted to 170mm but I can get 3 complete XD600s for the cost of the 170 Carmina crankarms. (yes I know, 170mm cranks seem incongrous with my height but I actually like them plus there is a ground clearance issue with longer cranks with the 650b conversion on my bike with 80mm BB drop) Consulting with Rivendell is something I should do. I don't probably think that I would get Grant if I called on the phone, but I have talked to several of the others before. I'll be leaving for the Bay Area in a week for 3CR and would like to visit the Rivendell World HQ anyway. I have the early part of the week before the ride available. On Wed, Jul 23, 2014 at 7:31 AM, Michael Hechmer <mhech...@gmail.com> wrote: > I use that campy FD on all my bikes, except the tandem which has a campy > SR. I find they shift superbly. I would be very reluctant to bend one, > since they don't make them any more.. > > When you wrote that you were at the limit of the set screw I wondered > about the chain line and if the BB was too long, but then you added that > you sometimes have trouble lifting the chain up to the big ring, and > dropping the chain below the small ring. Starting over from scratch is > probably a good idea but here are some of the things I've done over the > years that have improved front end shifting. > > Make sure the chain isn't too long. The shortest workable chain and the > shortest workable rear cage seems to produce the best front end shifting. > > I now use a "chain catcher" on all my bikes to prevent the chain from > falling inside the inner ring. I like the ones from Aceco, but there > certainly are cheaper ones that work as well. Sooner or later something > will come just a bit out of alignment and trigger this kind of chain drop, > > When replacing big rings I now insist on one with a post between the ring > and arm for the same reason, because sooner or later a chain will jump > across and fall onto the arm. At least with a post, there is no chance of > wrapping the chain. > > New rings shift better than old rings; good rings shift better than budget > rings; ramped and pinned rings shift better than plain rings. I know some > very smart people ( Grant Peterson, Jan Heine, & Peter White) think ramps > do not help, but I disagree. I wouldn't have thought so for my first 35 > years of cycling but then I bought a set of ramped TAs and thought OMG. The > ramped White Ind rings on my Ram also shift superbly. For the first two > years of riding our tandem I had all the front end shifting issues you > describe (plus not being able to drop the chain to the small ring), and > noticed at tandem rallies that it seemed to be the most common problem > among riders. Then I did all of the above and have not missed a shift on > the tandem since. > > I suspect that the ramps simply encourage the chain to drop onto the ring > when it may otherwise struggle to make good contact. > > Lastly, I would try to have the conversation with Grant. At least his > thoughts on ST angle and front shifting would be good to know. > > Michael > > > On Tuesday, July 22, 2014 11:13:40 AM UTC-4, Jim Bronson wrote: > >> I have had my Rivendell for approximately 9 years now. During this time I >> have continually had problems with overshifting of the front derailer. >> This has continued through 4 different cranksets, two or three different >> front derailers, different brands of chains, different casettes, different >> LBSs tinkering with it and so forth. Not to mention my own tinkering. >> I've theorized that maybe the seat tube angle on my bike is different than >> others due to the large size of my bike - 69cm, but I don't really know. >> >> I had given up on the problem and just rode the chain back on to the big >> ring if it came off that way, or stopped and put it back on the granny if >> it came off that way. >> >> I just recently as in last week switched to a Deore SGS derailer, so >> super long cage. With so much longer of a cage, it pulls the chain back a >> lot father now when it comes off the big ring and I am afraid of something >> catastrophic happening like the chain getting tangled up in the spokes. So >> there is a renewed urgency to do something about it. >> >> The current front derailer is a Campy Racing T, which from what I read on >> the Internet is supposed to be good at shifting compact triples. I am >> currently running a Sugino XD600 46/36/26 crankset and also using Shimano 9 >> speed bar ends. If it makes a difference. >> >> I read something on the 650B list about bending in the leading tip of the >> outer plate to prevent overshifting. I really don't want to trash a >> perfectly good front derailer but I'd be willing to try it if there was a >> reasonable expectation of it being successful. To quote: >> >> "On my last successful Ritchey crank build I used an NOS first generation >> Shimano deer head with said alignment and the leading tip of the outer >> plate bent in to better keep the 9spd chain from over shifting when coming >> back up onto the big ring." >> >> Or is there a different derailer model I should be using? I'm open to it. >> >> -- >> Keep the metal side up and the rubber side down! >> > -- > 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 post to this group, send email to rbw-owners-bunch@googlegroups.com. > Visit this group at http://groups.google.com/group/rbw-owners-bunch. > For more options, visit https://groups.google.com/d/optout. > -- Keep the metal side up and the rubber side down! -- 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 post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at http://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
