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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
