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  1. #1
    Senior Member triumph.1's Avatar
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    nuovo record FD problem

    I am really not familiar with the way this works in reality, but conceptually I get it. Today I shifted into the big ring and as I did it I notice it was shifting with difficulty. Being friction shift I pushed down a bit more and the chain went onto the big ring. When I went to down shift to the small ring the cable just went slack. It did appear the cable slipped. After the ride I looked the FD over and no adjustment moved anything. the limit screws didn't move the cage in or out cannot budge the thing to make the pivots work. It's like it is frozen, but it makes no sense to me. I took the FD off to clean it and inspect it closer, but I don't see where anything is wrong. Can anyone help me on this or kick me in the right direction, thanks.

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    From your description, it's either sticky pivots in the FD pantograph, or possibly the cable itself binding at the BB turnaround.

    The likelihood of the cable being the culprit depends somewhat on the age and setup of your bike. Older bikes had closed noodles which were very prone to rusting and binding. This is less of a problem with the newer open under the BB systems, but still possible.

    Start by isolating the problem. Slip the chain off the crank, and pull it backward at the bottom of the FD cage so it's not a factor. Shift the FD back and forth by pushing the lever arm itself (not the shift lever) and releasing, and see if the action is smooth. Repeat the same test by pulling the wire away from the downtube like a bow string, and see if it's still smooth, or you get the binding.

    If everything seems OK without a chain, then it's more complicated, and you need to review the entire FD mount. Possibly it slipped down and is too low to work right, or possibly a bit twisted.

    Do the diagnostic step by step, eliminating possibilities until you identify the problem, then correct that.
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  3. #3
    Andrew R Stewart Andrew R Stewart's Avatar
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    I think you answered your own question. "It's like it is frozen". Why wouldn't this make sense? The ft der is directly in the path of the fling off from the rear wheel. I'll bet you've rarely cleaned or lubed the pivots. A stiff pivot would explane both the hard shift out to the big ring as well as the lack of movement bacy (and the slack cable). When you took off the der did it move/pivot through the normal range or was it still "frozen"? IF the der moved then was it warm but when you were riding was it freezing cold? Ice could explane winter freezing but indoors function. (have seen the same with freewheels many times).

    Depending on the vintage the der might have an "e" clip on the end of one of the pivots that can be remover (watch that you don't loose it as it flys off...). The end of the spring will also have to be detatched from the end of it's pivot post position. Then the der should be able to be seperated into two sub assemblies. Each arm of the parallelagram can be moved during the solvent cleaning and relubing. Reassemble the two halves, reattach the spring end and clip if present. Now the der should move as intended for many more miles, or until it gets crummied up again.

    BITD this service was done every year or few thousand miles by those who cared for their bikes, along with the bearings and the rest of the moving parts. Andy.

  4. #4
    S'Cruzer pierce's Avatar
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    if you disassemble and clean the pantograph pivots as Andrew says, be sure to apply a thin layer of good waterproof grease on all bearing surfaces when reassembling. I usually use green marine waterproof bearing grease.


    here's a very sad and neglected NR front from the mid 70s.



    it still works fine as long as the cable is in good shape and lubricated.

  5. #5
    Senior Member Homebrew01's Avatar
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    Quote Originally Posted by triumph.1 View Post
    I am really not familiar with the way this works in reality,
    .the limit screws didn't move the cage in or out
    It just moves in and out, moving the chain as it goes... that's it
    The limit screws are not supposed to make it move. They just prevent it from moving too far.

    When you took the FD off, does it pivot if you move it by hand ? Clean it up, add a drop of lube on the pivot points & try again. You can also add a dab of grease to the cable where it goes around the bottom bracket.
    Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike

  6. #6
    Senior Member triumph.1's Avatar
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    I took it apart as much as needed to find the bottom pivot arm is seized. I could barely move it with a pair of channel locks but was able to isolate the problem. I had never had one of these apart before now so my understanding of their assembly was not clear. So I am hoping pb blaster into the arm will eventually break up some of the crud inside. I could try some heat to see if that helps speed up the process. As someone mentioned I have never cleaned the pivots. I bought the bike last fall and rarely ride it. The local LBS was paid to go through the bike clean and adjust so I assumed it would be good for awhile. Thanks for the input, I greatly appreciate the insight. Now back to breaking it free and then the reassembly. Learning this stuff is easier when I have experienced people to walk me through potential problems, thanks again everyone.

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    Quote Originally Posted by triumph.1 View Post
    I took it apart as much as needed to find the bottom pivot arm is seized. I could barely move it with a pair of channel locks but was able to isolate the problem. I had never had one of these apart before now so my understanding of their assembly was not clear. So I am hoping pb blaster into the arm will eventually break up some of the crud inside. I could try some heat to see if that helps speed up the process. As someone mentioned I have never cleaned the pivots. I bought the bike last fall and rarely ride it. The local LBS was paid to go through the bike clean and adjust so I assumed it would be good for awhile. Thanks for the input, I greatly appreciate the insight. Now back to breaking it free and then the reassembly. Learning this stuff is easier when I have experienced people to walk me through potential problems, thanks again everyone.
    If you have some kerosene, OMS, diesel fuel, or the like, pour some into a can or jar, and soak the FD overnight. You don't have to disassemble it first, but it's fine if you do. The overnight soak will loosen everything, making cleaning it much easier.
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    S'Cruzer pierce's Avatar
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    If that was mine, I'd take it off the bike, apply WD40 liberally and working it til it was free, and comes part, then more wd40 and a parts brush til it was all clean and shiny, then wipe it all off with a dry rag and grease the shaft and reassemble.

    do note, the spring on those is under a fair amount of tension.

  9. #9
    Senior Member triumph.1's Avatar
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    All is good. Got it worked loose, everything is clean and the FD is mounted back on the bike. Amazing how smooth it pivots now that it is clean. Well no day is lost if I learn something new, thanks.

  10. #10
    Andrew R Stewart Andrew R Stewart's Avatar
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    Quote Originally Posted by triumph.1 View Post
    I took it apart as much as needed to find the bottom pivot arm is seized. I could barely move it with a pair of channel locks but was able to isolate the problem. I had never had one of these apart before now so my understanding of their assembly was not clear. So I am hoping pb blaster into the arm will eventually break up some of the crud inside. I could try some heat to see if that helps speed up the process. As someone mentioned I have never cleaned the pivots. I bought the bike last fall and rarely ride it. The local LBS was paid to go through the bike clean and adjust so I assumed it would be good for awhile. Thanks for the input, I greatly appreciate the insight. Now back to breaking it free and then the reassembly. Learning this stuff is easier when I have experienced people to walk me through potential problems, thanks again everyone.
    Many shops don't take a proactive view to preventitive steps during tune ups. The time it takes to add a drop of lube (triflow in my usual process) on each pivot ,work it in and wipe off seems to be more then some want to take. Most shops/mechanics will leave "good enough alone". If the der was moving when they serviced it then that's to their advantage, no extra attantion needed, less time spent.

    Glad to hear that you figured things out and got the der working well. Now take your new found knowledge and apply it elsewhere on the bike. Any moving/pivoting part needs periodic cleaning and lubing. Andy.

  11. #11
    Senior Member triumph.1's Avatar
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    Andy, I did as you suggested and cleaned/lubed all moving parts. The bike shifts very nicely after adjusting. It does make sense what you said about most shops not performing the extra steps if things appear to be working.

  12. #12
    Senior Member southpawboston's Avatar
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    I don't know if this was typical for Campy NR FDs, but I have one whose pivots bind. I've done everything-- soaked in WD40, sonicated, greased. The pivots still bind and the return spring doesn't have enough tension to overcome the binding.

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    Quote Originally Posted by southpawboston View Post
    I don't know if this was typical for Campy NR FDs, but I have one whose pivots bind. I've done everything-- soaked in WD40, sonicated, greased. The pivots still bind and the return spring doesn't have enough tension to overcome the binding.
    IME that kind of binding is extremely rare. Pull it apart clean everything and put it back together with all pivots oiled and see if it still binds. If so, take it back apart and look for dings or burrs on the pivot arms and posts.
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  14. #14
    Senior Member southpawboston's Avatar
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    Quote Originally Posted by FBinNY View Post
    IME that kind of binding is extremely rare. Pull it apart clean everything and put it back together with all pivots oiled and see if it still binds. If so, take it back apart and look for dings or burrs on the pivot arms and posts.
    In my case the binding is occuring at the one pivot between the steel cage and the outer pivot arm. I've taken the entire FD apart insofar as can be done without removing the riveted pin that creates the pivot between the steel cage and alloy arm. All other pivots have been taken apart, cleaned, filed, polished, oiled, etc. It appears the "ears" of the steel cage that form the flanges for the pivot are too tight and compressing the pivot arm, and this is the one pivot that cannot be disassembled without destroying the pin. I have tried to wedge the fine edge of a stainless steel razor between junction of the "ears" and the arm to loosen the pivot, using a hammer to tap the wedge in, but with only marginal results. It still binds, but the spring has just enough tension to return the cage to the default position. However, if I'm trying to shift to the inner ring while the chain is under lateral tension (i.e., with me applying pedaling torque), the FD will not shift. Once I ease off on pedaling, it will complete the shift. So it works, but barely. I suspect it came from the factory this way but the spring tension was high enough to compensate. Perhaps with age the spring has weakened some, exposing the pivot defect. I think it's time to retire this derailleur.
    Last edited by southpawboston; 01-02-13 at 09:01 AM.

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    Quote Originally Posted by southpawboston View Post
    I It appears the "ears" of the steel cage that form the flanges for the pivot are too tight and compressing the pivot arm, and this is the one pivot that cannot be disassembled without destroying the pin. ..... However, if I'm trying to shift to the inner ring while the chain is under lateral tension (i.e., with me applying pedaling torque), the FD will not shift. Once I ease off on pedaling, it will complete the shift. So it works, but barely. I suspect it came from the factory this way but the spring tension was high enough to compensate. Perhaps with age the spring has weakened some, exposing the pivot defect. I think it's time to retire this derailleur.
    FD's don't wear tighter, nor do spring constants change materially over time, so I think we need to clear the air and identify the actual problem.

    First three questions, has this FD been working on the same bike, and later stopped working? Were there any other changes, ie. remoe and remount, bike,new chainring, etc.? Are you comparing this bike's shifting to a modern one with shift gates on the outer ring?

    Start by seeing if the FD works right if there's no chain. Slip the chain off the ring and pull it back off the bottom of the cage so it doesn't touch the rings, and see if the FD shifts back and forth OK.

    If so then the FD is OK, and the issue is the position or possibly your shift practices and expectations. FDs are different from RDs in that work on the tension side of the chain, and therefore pedaling pressure can keep the chain too tight to lift off the teeth and shift. Also if the FD is pushing on the chain too far forward the chain's stiffness can support the cage against the ring's teeth so the spring can't push it. The shift gates on the outer ring help overcome this somewhat, but even then poor position or excess tension will prevent a shift.

    If it won't shift smoothly without a chain apply a bit of lapping compound to what you suspect to be the problem area and work the derailleur back and forth a while until it frees up. When finished be sure to wash all the compound off and lubricate properly.
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  16. #16
    Senior Member southpawboston's Avatar
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    Quote Originally Posted by FBinNY View Post
    FD's don't wear tighter, nor do spring constants change materially over time
    I'm not a metallurgy expert, but then why do you see springs weaken? From repeated cycles of movement? Why do you see car springs sagging over time?

    Quote Originally Posted by FBinNY View Post
    First three questions, has this FD been working on the same bike, and later stopped working? Were there any other changes, ie. remoe and remount, bike,new chainring, etc.? Are you comparing this bike's shifting to a modern one with shift gates on the outer ring?

    Start by seeing if the FD works right if there's no chain.
    I got this RD used with unknown history. At the bench, and on the bike with no chain, it returned to its rest position without manual intervention, so I assumed it was functioning correctly.

    Quote Originally Posted by FBinNY View Post

    If so then the FD is OK, and the issue is the position or possibly your shift practices and expectations. FDs are different from RDs in that work on the tension side of the chain, and therefore pedaling pressure can keep the chain too tight to lift off the teeth and shift. Also if the FD is pushing on the chain too far forward the chain's stiffness can support the cage against the ring's teeth so the spring can't push it. The shift gates on the outer ring help overcome this somewhat, but even then poor position or excess tension will prevent a shift.
    I've never had an FD that couldn't pull a chain off the large ring concurrent with a slight amount of pedaling torque. Of course, I don't shift under hard load, but I do shift regularly with a nominal load. All my other bikes can handle this transition, and the FD that I had previously on this same bike with the same chain and chainrings (a Huret Jubilee FD) had no problems whatsoever. I switched FDs because I wanted the Jubilee on another bike.

    I've never ridden a bike with modern ramps and pins on the chainrings; I've only ridden vintage cranksets with vintage FDs. My most "modern" setup is a 1st gen Shimano 105, and even that doesn't have shift aids. As I said earlier, ONLY this FD is having trouble moving a chain off the large cog. I should have clarified that this same bike had seen other FDs with an otherwise identical setup, and not had the problem. I really think it's the binding pivot that's the problem here.

  17. #17
    S'Cruzer pierce's Avatar
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    car spring sag is usually caused by worn out bushings and/or shocks rather than actual spring fatigue.

  18. #18
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    Quote Originally Posted by southpawboston View Post
    I'm not a metallurgy expert, but then why do you see springs weaken? From repeated cycles of movement? Why do you see car springs sagging over time?
    Springs retain their constant through hundreds of thousands of cycles. If that weren't true, most of the scales we see would have to be recalibrated all the time. What kills springs and make them sag is flexing beyond their limits, which distorts the spring. You see this in cars, the springs last the life of the car without sag, unless the car is routinely abused and overloaded which will sag the springs.

    Staying with the scale analogy, a 120# woman can get on and off the bathroom scale forever and it'll always stay accurate. But if a 400# man steps on it once, he'll overload it and it won't zero out. But the spring constant is unchanged, and if it's zeroed out it'll be accurate again.

    Since derailleurs have limited travel between fixed stops it's impossible to overload and weaken the spring.



    Quote Originally Posted by southpawboston View Post
    I got this RD used with unknown history. At the bench, and on the bike with no chain, it returned to its rest position without manual intervention, so I assumed it was functioning correctly.
    A valid assumption, and I suspect the RD is fine, and something else is the root of the problem.



    Quote Originally Posted by southpawboston View Post
    I've never had an FD that couldn't pull a chain off the large ring concurrent with a slight amount of pedaling torque. Of course, I don't shift under hard load, but I do shift regularly with a nominal load. All my other bikes can handle this transition, and the FD that I had previously on this same bike with the same chain and chainrings (a Huret Jubilee FD) had no problems whatsoever.

    I've never ridden a bike with modern ramps and pins on the chainrings; I should have clarified that this same bike had seen other FDs with an otherwise identical setup, and not had the problem. I really think it's the binding pivot that's the problem here.
    It might be a binding pivot, but then you'd see some sign of that without the chain also.

    My best guess without seeing it is that the cafe is pushing the on the chain too close (or overlapped) to the chainring. Picture a clothesline on a pulley. You want to derail the line as it runs onto the pulley, so you push on the line a bit back from the pulley and over it goes. But if you push on the line too close to the pulley the flange supports the line and you can't derail it because you're pushing against the pulley flange.

    Likewise the FD. It has to push the chain back a bit from where it's engaged, otherwise the teeth will resist the cage movement. It's possible that your cage is bent a bit, and the front is pushing the chain where it's engaged to the chainring. Test this theory by bringing the heel in so the back of the cage touches the chain before the front. If that improves the downshift then you know the FD is OK, and it's a matter of fine tuning the FD position and angle.
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  19. #19
    Senior Member Road Fan's Avatar
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    Quote Originally Posted by Andrew R Stewart View Post
    Many shops don't take a proactive view to preventitive steps during tune ups. The time it takes to add a drop of lube (triflow in my usual process) on each pivot ,work it in and wipe off seems to be more then some want to take. Most shops/mechanics will leave "good enough alone". If the der was moving when they serviced it then that's to their advantage, no extra attantion needed, less time spent.

    Glad to hear that you figured things out and got the der working well. Now take your new found knowledge and apply it elsewhere on the bike. Any moving/pivoting part needs periodic cleaning and lubing. Andy.
    I also believe that many shops don't pay attention to real problems in older bikes, "not caring" if they hasten the demise of the bike and a subsequent new bike sale.

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    Quote Originally Posted by Road Fan View Post
    I also believe that many shops don't pay attention to real problems in older bikes, "not caring" if they hasten the demise of the bike and a subsequent new bike sale.
    I don't think it's that shops don't care, it's simply that they don't know, and don't know that they don't know.

    Compare the the rate of change in bike hardware, to the average age, experience and staff turnover of the mechanics working and it's easy to see how knowledge can get lost in translation.

    A few years back Ed Nasjleti od Sram commented to me that it wouldn't be long before there'd be some pro bike mechanics who'd never removed a quill stem. About a year ago his prediction came true when I was in a shop, and the young mechanic had no idea how to loosen a quill stem on a bike brought in for a new headset. Add stems to cotter pins on the list of "lost" technologies.

    Mechanics used to working with things like Hyperglide, and gated shifting in general, aren't used to dealing with some of the older stuff.
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  21. #21
    Senior Member southpawboston's Avatar
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    Here's a picture of the FD. It's not the best angle to see it, but you can get an idea:



    I get your clothesline analogy perfectly (and it's a good analogy). I forgot to mention, I could feel the binding when I dismantled the FD and removed the spring. At about the middle of the range of the cage travel there was considerable resistance. Once overcome, the cage could continue to the end of its travel. It wasn't a completely free-swinging mechanism.

    Quote Originally Posted by FBinNY View Post
    Springs retain their constant through hundreds of thousands of cycles. If that weren't true, most of the scales we see would have to be recalibrated all the time. What kills springs and make them sag is flexing beyond their limits, which distorts the spring. You see this in cars, the springs last the life of the car without sag, unless the car is routinely abused and overloaded which will sag the springs.

    Staying with the scale analogy, a 120# woman can get on and off the bathroom scale forever and it'll always stay accurate. But if a 400# man steps on it once, he'll overload it and it won't zero out. But the spring constant is unchanged, and if it's zeroed out it'll be accurate again.

    Since derailleurs have limited travel between fixed stops it's impossible to overload and weaken the spring.





    A valid assumption, and I suspect the RD is fine, and something else is the root of the problem.





    It might be a binding pivot, but then you'd see some sign of that without the chain also.

    My best guess without seeing it is that the cafe is pushing the on the chain too close (or overlapped) to the chainring. Picture a clothesline on a pulley. You want to derail the line as it runs onto the pulley, so you push on the line a bit back from the pulley and over it goes. But if you push on the line too close to the pulley the flange supports the line and you can't derail it because you're pushing against the pulley flange.

    Likewise the FD. It has to push the chain back a bit from where it's engaged, otherwise the teeth will resist the cage movement. It's possible that your cage is bent a bit, and the front is pushing the chain where it's engaged to the chainring. Test this theory by bringing the heel in so the back of the cage touches the chain before the front. If that improves the downshift then you know the FD is OK, and it's a matter of fine tuning the FD position and angle.

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    Quote Originally Posted by southpawboston View Post
    ....I forgot to mention, I could feel the binding when I dismantled the FD and removed the spring. At about the middle of the range of the cage travel there was considerable resistance. Once overcome, the cage could continue to the end of its travel. It wasn't a completely free-swinging mechanism.
    It's possible that the body is damaged so the 2 pins aren't perfectly parallel now. Another place to look is where the legs of the spring meet the cage and arm. When the FD moves the leg slides a bit against the stop. Possibly a groove or notch was worn in there.

    I suggest you take it off the bike, and work the mechanism in your hand and see if you can spot exactly where and why it sticks. Some times these respond well to a bit of manhandling, twist the cage back and forth against the body, and it might settle back home.
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    Quote Originally Posted by FBinNY View Post
    It's possible that the body is damaged so the 2 pins aren't perfectly parallel now. Another place to look is where the legs of the spring meet the cage and arm. When the FD moves the leg slides a bit against the stop. Possibly a groove or notch was worn in there.

    I suggest you take it off the bike, and work the mechanism in your hand and see if you can spot exactly where and why it sticks. Some times these respond well to a bit of manhandling, twist the cage back and forth against the body, and it might settle back home.
    Good points. I hadn't thought of either of those.

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    might just be some grit wedged in there somewhere, and liberally flushing it with wd-40 while working the mechanism back and forth by hand will sort it out.

    dry off the excess WD40 and apply a proper oil afterwards, or grease on the removable pivots.

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