Strange Shimano ultegra gear shifter intermittent failure

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  • #26144
    terrycojones

    I have an Ultegra groupset and have been experiencing weird intermittent shifter failures and am wondering if anyone else has had the same thing or if people can suggest a possible cause.

    The problem occurs every now and then (half a dozen times on a 120km ride last weekend). The symptom is that on my right shifter (controlling the rear cassette), shifting to a higher (i.e., smaller cog) gear sometimes becomes impossible. The shift lever can be pushed to the left and doesn’t encounter any resistance – no “click” feel when the gear change is initiated, nothing.

    This happens frequently when I have been out of the seat on a climb. I’ll get to the crest of the hill and will go to change up a gear and… nothing. So I’m stuck in the low gear, spinning faster and faster as the road levels out.  It doesn’t always happen after climbing, sometimes it will happen under a fairly normal cycling load on the flat. It just seems that the added power increases the likelihood of the shifter dropping out, but I don’t see how that could be. None of it makes sense to me though, so I mention it.

    I don’t have a way of fixing the shifter. I’ve tried changing to an even lower gear, changing to the small front ring, getting off the bike and moving the rear derailleur around by hand. What works is just to wait – somewhere between 30 seconds and a few minutes – and the shifter returns to normal.

    Last weekend I installed a brand new rear cassette, a new derailleur and a new chain (all of this for other reasons) but the problem persists. So it seems like the problem must be with the shifter, but what could it be?

    There’s one thing I’ve done which I’m told I shouldn’t have: occasionally spray some WD40 into the shifters. Apparently this can cause a residue build up. Maybe that’s somehow occasionaly causing the shifter to drop out?

    I made a couple of videos of the shifter in its non-functioning state, which do a better job of showing what’s going wrong than all the above words: http://jon.es/other/chris1.mp4 and http://jon.es/other/chris2.mp4

    Thanks for any help / suggestions!

    Terry

Viewing 15 replies - 1 through 15 (of 23 total)
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  • #876775
    0
    srchar

    Use Gorilla Snot underneath

    Use Gorilla Snot underneath the hoods. You can get it from guitar shops – its intended use is to stop plectrums slipping out of guitarists’ fingers.

    Hairspray will also do the job for a little while but requires frequent reapplication.

    #876773
    0
    Roadie_john

    I had the same problem with a

    I had the same problem with a Tiagra 4700 front shifter. Definitely a ratchet issue. Warranty replacement from Ribble. Sorted. No bother. 

    #876771
    0
    . .

    I don’t think new hoods would

    I don’t think new hoods would help.  Mine were only two months old when I first had the problem.  If you give the hoods some welly on a climb, they will slip.  Gorilla Glue works a treat, but be careful to keep it away from the moving parts (not forgetting it expands to three times the volume as it sets)

    Pretty poor design by Shimano really

    #876769
    0
    terrycojones

    Mystery solved!

    Mystery solved!

    It was the hood. It was tending to slide forward and also to twist. When it’s forward it has a tendency to catch a small part of the shifter and prevent it from returning to its normal position. It will stay like that indefinitely. I guess when the no-shift problem was happening to me I would eventually pull the hood back or straighten it and release the pressure, releasing the part that was stuck.

    I took some photos to illustrate in case this helps someone in the future. http://jon.es/other/sti-hood-1.jpg shows what things should look like (I mean if the hood were in place correctly, this is what it would look like underneath). In http://jon.es/other/sti-hood-2.jpg with my finger I’m slightly moving the part that would normally be pushed inward and upward by the small shifter (the one that shifts to a higher (faster) gear). That part gets moved through about 45 degrees by the shifter and would normally return to its starting position (see 1st photo). But if your hood is pushed forward, as in http://jon.es/other/sti-hood-3.jpg then the rubber of the hood can hold the part in place and it doesn’t return to its normal downward-pointing position. During that time your shifter can be pushed all the way to the left without meeting any resistance (no “click” as a gear change is triggered (as shown in the videos in the original post above)). If you then move the hoods forward into their correct position, as in http://jon.es/other/sti-hood-4.jpg the small part is released and springs back into its normal position.

    So I guess I need to find a way to keep my hoods in place properly. They’re stretched, so the various little knobs they have on their insides don’t sit properly in the corresponding indents in the shifter. It’s either tape, or glue, or new hoods I guess.

    Thanks for all the help everyone! That was really great 🙂  I had no idea what the problem was…

    #876767
    0
    terrycojones
    I am a human wrote:
    I can recreate your symptom by moving the brake lever as if I’m downshifting to an easier gear, then carrying on the movement with the upshift lever – it then encounters no resistance and moves the whole length of the lever throw.  Is there something that’s making the brake lever move inward at the same time as the upshift lever?

    No, the brake lever isn’t being moved at all. Thanks!

     

    #876765
    0
    terrycojones
    . . wrote:
    Duncanap wrote:
    It may not be relevant but I had something similar when my hoods (the rubber covers) stretched and moved.

    i seemed like the hoods were providing the return spring so you could shift once but the would just get a soft lever.

    could be worth a check.

    I had the same problem. There’s a small lever that pushes against the hood, and when the hood slipped, the lever would get stuck.   The lever is just above where your thumb sits when riding on the hoods, and I found I could push it back with my thumb when it got stuck.

    The problem is now solved by Gorilla-gluing the hoods in place.  Not sure if Shimano would approve, but it works.

    OK, I’m going to take a close look. Thanks very much. I couldn’t come up with a reason why standing up out of the seat (normally on hills) could be so well correlated with the problem occurring. But when I stand up to climb, I pull up on the handlebars with my hands wrapped around the base of the hoods, and they do get moved. Particularly the right one gets rotated quite a lot (45 degrees sometimes). It could be that my shifters have a grease problem, but that would strike more consistently or randomly (not well correlated with hill climbing), but it seems more likely now that it’s the hoods.  I’m going to look right now…..

    Thanks again!

    #876763
    0
    I am a human

    I can recreate your symptom

    I can recreate your symptom by moving the brake lever as if I’m downshifting to an easier gear, then carrying on the movement with the upshift lever – it then encounters no resistance and moves the whole length of the lever throw.  Is there something that’s making the brake lever move inward at the same time as the upshift lever?

    #876761
    0
    stevie63
    Duncanap wrote:
    It may not be relevant but I had something similar when my hoods (the rubber covers) stretched and moved.

    i seemed like the hoods were providing the return spring so you could shift once but the would just get a soft lever.

    could be worth a check.

     

    When I first set up 5800 levers on my bike the same thing happened until I realised that the hoods were snagging slightly underneath. Straightened them up and no problems ever since.

    #876759
    0
    . .
    Duncanap wrote:
    It may not be relevant but I had something similar when my hoods (the rubber covers) stretched and moved.

    i seemed like the hoods were providing the return spring so you could shift once but the would just get a soft lever.

    could be worth a check.

    I had the same problem. There’s a small lever that pushes against the hood, and when the hood slipped, the lever would get stuck.   The lever is just above where your thumb sits when riding on the hoods, and I found I could push it back with my thumb when it got stuck.

    The problem is now solved by Gorilla-gluing the hoods in place.  Not sure if Shimano would approve, but it works.

    #876757
    0
    terrycojones
    Duncanap wrote:
    It may not be relevant but I had something similar when my hoods (the rubber covers) stretched and moved.

    i seemed like the hoods were providing the return spring so you could shift once but the would just get a soft lever.

    could be worth a check.

    Actually, my hoods do move around a lot now (following a bike service & new bar tape being added). But the problem was happening before the hoods started to move about. I will take a look though. The difficulty is that I only occasionally have the problem – it’s not easy to reproduce (hence the videos in my original posting – at my LBS I couldn’t get the problem to occur, so had to film it in the wild).

    Thanks!

    #876755
    0
    terrycojones
    Tjuice wrote:
    Like everyone above has said, I would have said

    1) Is it possible that cables are not moving freely enough

    2) Possibility that the grease in the shifter has got too sticky and is stopping the mechanism working properly. 

    Re: the latter, do you find you have more problems when it is cold and fewer problems when it is baking hot?  Try heating up the shifter with a hairdryer for a few minutes (worth peeling back the hoods first to stop them insulating your attempts) – does that make the shifter work better?  If so, it could well be gummed up grease (heating it up can make it less viscous and sticky).

    I had a problem that sounds extremely similar to yours a number of years back with some Shimano RSX shifters.  Despite the warnings that these are not user-servicable and should not be taken apart, I decided that I had nothing to lose, and I was pretty confident of my ability to put back together something mechanical that I had taken apart (I have quite a bit of experience of dismantling/repairing/re-building a variety of mechanical things).

    I found that it was entirely possible to dismantle the shifter very carefully and found that there was some very, very thick old grease in there.  I thoroughly cleaned everything, and then re-greased with something much less viscous and put it all back together again.  Shifters have been faultless since then.  I just wish I could get some replacement hoods for them!

    Good luck finding a solution

    Hi TJuice

    I don’t think it’s the cable. There’s a new cable in there and the shifting is just like when the bike was new. The problem I have only arises occasionally – 99% of the time the shifter works great. I think if it were a cable problem I’d have it all the time.

    I’m guessing gummed up grease is probably the culprit, as you suggest. I’ve not noticed a hot/cold difference – hadn’t thought about it. If I can’t fix it with cleaning I might take it apart (and take photos along the way so I can put it back together). I have to wait for some lube & grease to arrive before I try though.

    Thanks again!

    #876753
    0
    terrycojones
    kenyond wrote:
    My tiagra 4700’s wont shift if they have been pulled back a bit as if I was using the brakes, like you say theres no click or anything, you may have a little grit stopping it going back and not engaging the ratchet for gear changes

    Thanks. Hopefully giving them a good clean, as in the videos recommended by @TypeVertigo, will get things working again.

    #876751
    0
    terrycojones
    TypeVertigo wrote:
    terrycojones wrote:
    @TypeVertigo – thanks, that sounds super helpful, and like it could be the cause. I’d never even heard of pawls. I should probably play more Scrabble 🙂 Anyway, I’ll go track down the Art’s Cyclery video.

    Allow me to help point you in the right direction.

    https://www.youtube.com/watch?v=9657OoOY3oE

    The video shows SRAM DoubleTap levers, and the products used are White Lightning Clean Streak for cleaning (vs WD40) and Slick Honey + Boeshield T-9 for relubrication (vs regular Shimano grease + Tri-Flow Superior Soy Lube), but it’s still basically the same method.

     

    There’s also “RJ the Bike Guy,” another YouTube channel. RJ’s hobby is buying old or inoperative bikes and restoring and/or upgrading them to modern drivetrains; some of these projects he keeps while the rest he sells. He mentions the WD40 fix a lot, and he has so many videos detailing the technique – below is one of them. The fix works even with flat-handlebar MTB trigger shifters.

    https://www.youtube.com/watch?v=JbgsJRt-h1A

    https://www.youtube.com/watch?v=49lAdo_vUX4

    I hope this helps.

    Thanks TypeVertigo!  I’d found the first after your original reply, and just watched the two from RJ. I have a couple of products on order & will give it a shot as soon as they arrive…

    #876749
    0
    kenyond

    My tiagra 4700’s wont shift

    My tiagra 4700’s wont shift if they have been pulled back a bit as if I was using the brakes, like you say theres no click or anything, you may have a little grit stopping it going back and not engaging the ratchet for gear changes

    #876747
    0
    Tjuice

    Like everyone above has said,

    Like everyone above has said, I would have said

    1) Is it possible that cables are not moving freely enough

    2) Possibility that the grease in the shifter has got too sticky and is stopping the mechanism working properly. 

    Re: the latter, do you find you have more problems when it is cold and fewer problems when it is baking hot?  Try heating up the shifter with a hairdryer for a few minutes (worth peeling back the hoods first to stop them insulating your attempts) – does that make the shifter work better?  If so, it could well be gummed up grease (heating it up can make it less viscous and sticky).

    I had a problem that sounds extremely similar to yours a number of years back with some Shimano RSX shifters.  Despite the warnings that these are not user-servicable and should not be taken apart, I decided that I had nothing to lose, and I was pretty confident of my ability to put back together something mechanical that I had taken apart (I have quite a bit of experience of dismantling/repairing/re-building a variety of mechanical things).

    I found that it was entirely possible to dismantle the shifter very carefully and found that there was some very, very thick old grease in there.  I thoroughly cleaned everything, and then re-greased with something much less viscous and put it all back together again.  Shifters have been faultless since then.  I just wish I could get some replacement hoods for them!

    Good luck finding a solution

Viewing 15 replies - 1 through 15 (of 23 total)
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