Shimano Ultegra Front Shifter Problem

Discussion in 'Cycling Equipment' started by vansiclenr, Oct 22, 2003.

  1. vansiclenr

    vansiclenr New Member

    Joined:
    Oct 7, 2003
    Messages:
    2
    Likes Received:
    0
    My Ultegra STI shifter for the front derailleur is slow to shift up to the big ring (double, not triple) requiring a lot of cranking: One or two big cranks, hold halfway, then another crank. Then, once it's on the big ring, it won't shift down. I can usually fix this by grabbing the wire next to the down tube and yanking while I try to shift. This rather defeats the purpose of STI!

    I replaced the cable, lubed everything, re-did the set up several times (taking the tension off the cable by releasing it from the lock screw on the derailleur, backed the set screws all the way off, then re-tensioned the whole thing).

    Beyond replacing the cable, I haven't messed with the shifter itself. All the magazines suggest avoiding these fussy mechanism with its 100 parts. But I'm willing to try.

    All ideas welcomed. Thanks.

    Van
     
    Tags:


  2. drewski

    drewski New Member

    Joined:
    Oct 20, 2003
    Messages:
    342
    Likes Received:
    0
    when you say a lot of cranking, you mean revolutions of the crankset? like 3 whole revolutions? does this happen everytime you try and shift or just while shifting under load?

    imo, this doesn't sound like a shifter issue since going to the big chainring is just pulling the cable. i'd say that either your chainrings/chain are worn and so the little pins and stuff aren't engaging right, or your front deraileur is either worn and the cage has lost some rigidity to properly push the chain over or not tightened enough to the seat tube.

    the first scenario is, imo, less likely since even before those little pins came about 3 revolutions to shift was excessive. try comparing your deraileur to another by gently pushing the cage side to side to see if there is significantly more "play". they do wear out over time and use. easy test, swap the FD and try the shifting again.

    the downshifting issue could also be the deraileur. either the cage issue or a worn out spring could cause the inability to downshift without assistance.

    i'm hoping it's your deraileur as it's a lot cheaper to replace than the shifters!
     
  3. vansiclenr

    vansiclenr New Member

    Joined:
    Oct 7, 2003
    Messages:
    2
    Likes Received:
    0
    Thanks, Drewski. I was unclear. I meant cranking on the brake/shift lever itself. Any push of the shift/brake lever pushes the chain up onto the big chainwheel, but it pops right back. To get it to stay, I have to push the brake lever/shifter firmly to the left a couple of times, then back off halfway and push hard again. Then it's stuck about half the time. Clicking the smaller lever to drop it off the ring has no effect, no "Click" feeling on my hand, no movement on the derailleur.

    Yup, I also hope it is something I can fix before I have to replace the $150 -$200 shift/brake mechanism!

    Van
     
  4. daveornee

    daveornee New Member

    Joined:
    Sep 18, 2003
    Messages:
    2,763
    Likes Received:
    0
    Did you replace the cable housing with Shimano SIS housing?
    Check out the section of Sheldon Brown's web site on cables at URL:
    http://sheldonbrown.com/cables.html
    Pay particular attention to finishing the ends to make them look like the ones you see in Sheldon's "good" picture. A Dremmel tool with a "cut-off wheel" makes a nice clean end with very little practice. Just make sure the lining is also wide open.
    Check to make sure the cable is in the slot under the bottom bracket. Make sure that the cable to plastic bottom slot is at least very smooth and clean. I use a very small amount of teflon bearing grease on the cable at that juncture.
    Try the shifter action with the cable disconnected from the front derailer; just holding it under tension in your hand. The housing should provide just a passage way, with virtually no friction.
    If the cable is frayed or binds anyhere, you should replace it again. Check the cable route between the bottom bracket and the attachment to the front derailer. Make sure that it isn't impeded on any of it's route.
     
  5. tomasbikes

    tomasbikes New Member

    Joined:
    Aug 31, 2003
    Messages:
    19
    Likes Received:
    0
    My advice on "messing" with the shifter - don't even try. I can send you the bits and pieces from a RH Ultegra lever as evidence.

    I have an Ultegra RH lever that upshifts fine but requires the brake lever to be held in position while downshifting; the ratchet doesn't hold it in place. Any ideas out there?

    Tom C., La Grange, IL, USA
     
  6. boudreaux

    boudreaux New Member

    Joined:
    Oct 16, 2003
    Messages:
    5,133
    Likes Received:
    0
    Housing brand does not matter.Generic works as well.Go to www.parktool.com and check derailer adjustment.Statr at the beginning,not somewhere in the middle.
     
  7. boudreaux

    boudreaux New Member

    Joined:
    Oct 16, 2003
    Messages:
    5,133
    Likes Received:
    0
     
  8. boudreaux

    boudreaux New Member

    Joined:
    Oct 16, 2003
    Messages:
    5,133
    Likes Received:
    0
    nm
     
  9. boudreaux

    boudreaux New Member

    Joined:
    Oct 16, 2003
    Messages:
    5,133
    Likes Received:
    0
    Check the upper backside of the levers for a very small screw that holds them together.Lots of shifting problems caused by a loose or missing screw. Otherwise, if the shifters get crudded up and problems are not curable by derailer adjustment or change of cable/casing,hose them out with something like wd-40 and relube with a spray like triflow..And,yeah to not trying to take them apart.
     
Loading...
Loading...