Shifting problems... going mad

JimboPlob
JimboPlob Posts: 397
edited August 2012 in Workshop
Ok,

So I have a caad9 with Dura Ace. the problem is, the shifting is sh*t. I have replaced the chain, cassette, cables (inners and outers), rear mech and tweaked to my hearts content... But still, there is some horrible shifting problems. It takes an age to go either up or down a gear. An I often click to go to a smaller sprocket at the back and nothing happens. Going the other way is just as bad and often requires a bit of extra persuasion from the lever

I have set-up many bikes, and my recent winter hack which I fitted with second hand tiagra parts shifts flawlesly.

It seems like some sort of sticky cable, but I have re-cabled it twice already. Could it be the shifters themselves causing the issue??

The hanger also looks straight and true..

Im going mad!!

Any advice welcome.

Thanks

Comments

  • getprg
    getprg Posts: 245
    I too have tiagra on winter bike and dura ace on summer and tbh find tiagra much easier to set up than DA. DA seems to work to much finer tolerances.

    A couple of ideas to explore:

    If you've swopped inners 3 times could the problem be the outers? EG Were the cuts to the outers clean and are they still round or could they have been bent in the process of holding whilst cutting?

    I might be dreaming this but IIRC don't Shimano produce special finer (aka narrower) cables for DA - perhaps I really did just dream that up but I seem to remember oredering different (inevitably more expensive!) cables for DA last time.
  • JimboPlob wrote:
    The hanger also looks straight and true..

    Having tried all that you have, I would be tempted to take it to a bike shop and get them to check this (or get something like a park tool DAG2 and do it myself)

    As already mentioned, DA should really be run with PTFE inners, and SP41 outer cables, with matching ferrules.
  • Mike03776
    Mike03776 Posts: 40
    What's the length like on the outter that feeds to the rear mech? If it's too long/too short it could be causing the cable to stick.
  • JimboPlob
    JimboPlob Posts: 397
    I made it bigger rather than smaller. Its quite long but nothing drastic.

    Could the shifters themselves be at fault (durace ace 7800).

    I also notice that the gear shifts better at the back when I'm in the small ring as compared to the big ring (still not perfect though).

    Thanks
  • Mike03776
    Mike03776 Posts: 40
    Just of interest, what type of bottom bracket have you got, and what's the chainline like, though this shouldn't really be a huge factor, although it is probably why there is a difference between shifting on the big ring and the small ring. Dura ace is notoriously more difficult to set up than other group-sets. I'd just give you cable a decent amount of grease if that fails then I don't really have anymore suggestions without actually being able to see the bike.
  • Yossie
    Yossie Posts: 2,600
    All cables at the shifter end running nice and clean - ie no sharp bends/snags/weird routing to make the cable foul?

    Actual cables themselves shouldn't make a difference: I use D/A on the dry communter/fast training bike with the cheapo standard Shimano cables from the big box in the LBS (the £1.50 each ones) and it shifts faultlessly.
  • JimboPlob
    JimboPlob Posts: 397
    ultegra bottom bracket, 7800 cranks, reach meach, front mech and shifters..

    Cables are new, have replaced them twice.
  • Mike03776
    Mike03776 Posts: 40
    Either they're damaged, or you're set it up incorrectly. I'd be inclined to ask a technician at a local bike shop to have a quick look over to see what they think.

    Sorry I can't be of any further help,

    Mike
  • Yossie
    Yossie Posts: 2,600
    Just out of interest, is a technician the same as a mechanic or do I have to specify which one I want when I take my bike to the shop? I just need to know so that I don't ask for the wrong thing.
  • Mike03776
    Mike03776 Posts: 40
    Pretty much the same thing, different places just give them different titles.
  • Yossie
    Yossie Posts: 2,600
    Cool, just needed to make sure - thankyou very much.

    Kr

    Y
  • Just a couple of ideas. Have you checked your derailleur hanger is attached to the frame tightly? Also, depending on the design, you might need to make sure the rear quick release skewer is done up nice and tight as that helps keep everything in place.
  • mrdsgs
    mrdsgs Posts: 337
    make sure you have connected the rear mech cable to the correct side of the pinch bolt. there is usually a groove in the washer.
    Colnago Addict!
  • Bozman
    Bozman Posts: 2,518
    I've had 7800 for years on one bike and it's faultless full stop, but...... the only issue i've had was the rear derailleur cable started to fray inside the shifter, this caused a s**t load of problems before i figured it out, it was working fine it wasn't, it'd change down fine but i'd have issues changing up, it took 90 bloody minutes of cursing to sort that out.
    I did teach me the ins and outs of a rear derailleur though.
  • gaddster
    gaddster Posts: 401
    Are all your cassette sprockets on correctly?
    ARTHUR
    "Hello oh great one"
    LARRY
    "Are you talking to me or my ass?"
  • JimboPlob
    JimboPlob Posts: 397
    I Think I will start from scratch again once I have replaced the rear hanger. Should a bike shop be able to tell me if the current one is bent free of charge? Or is it worth just buying a new one?

    Thanks
  • Mike03776
    Mike03776 Posts: 40
    Yeah, that is no problem at most bike shops.
  • onbike 1939
    onbike 1939 Posts: 708
    JimboPlob wrote:
    I Think I will start from scratch again once I have replaced the rear hanger. Should a bike shop be able to tell me if the current one is bent free of charge? Or is it worth just buying a new one?

    Thanks

    Rather than spend £25 if you have a spare wheel you can use this to check if the Hanger is plumb. Unscrew the Rear Der. and screw in the threaded axle on the spare wheel which should be the same thread. You can then tell if the spare wheel is parallel or not. Measuring between them will give the exact distance and direction that you need to lever the spare wheel in order to achieve the correct position.
  • JimboPlob
    JimboPlob Posts: 397
    JimboPlob wrote:
    I Think I will start from scratch again once I have replaced the rear hanger. Should a bike shop be able to tell me if the current one is bent free of charge? Or is it worth just buying a new one?

    Thanks

    Rather than spend £25 if you have a spare wheel you can use this to check if the Hanger is plumb. Unscrew the Rear Der. and screw in the threaded axle on the spare wheel which should be the same thread. You can then tell if the spare wheel is parallel or not. Measuring between them will give the exact distance and direction that you need to lever the spare wheel in order to achieve the correct position.

    I am utterly lost by your post, I cant picture it...

    I am starting to think the drop-outs might be a little bent or something. Its a CADD9, and I notice that when the rear wheel is snug in the drops, the wheel looks closer to one side of the frame. I have tried various wheels, and they all seem to do it.

    If the drop-outs are bent, can it be corrected? Seems to ride fine, just doesn't shift well!!

    A
  • keef66
    keef66 Posts: 13,123
    Don't go trying to 'straighten' the dropouts on an alu frame, you risk breaking them off!

    I have read about the spare wheel tip before. Take off the rear derailleur and screw in the threaded end of the spare wheel's axle instead. So you have a second wheel mounted on the outside of the bike where the rear mech used to be. If your mech hanger is bent, the spare wheel won't be parallel to the normal one
  • JimboPlob
    JimboPlob Posts: 397
    Dumb question. DO I take the QR skewer out of the wheel and then screw the spare wheel into the rear mech hanger?
  • JimboPlob wrote:
    Dumb question. DO I take the QR skewer out of the wheel and then screw the spare wheel into the rear mech hanger?

    Correct. It is the spare wheel axle (or more accurately the threaded "spindle" that should be screwed in the hanger. You will have the spare wheel in parallel with your original and any discrepancy should be obvious (you can measure from the spare to the other wheel. It's a simple job to check this when using the correct tool and a bike shop will have one of these. Re drop-outs, I would doubt if these are out of alignment but again there is a tool to check this. Check by trying the wheel in position without the chain and pulling the wheel fully upwards (vertical drop-outs) or fully to the rear (horizontal drop-outs) and check if the wheel is square when in this position. More likely is that the wheel is not correctly positioned in the drop-outs which will cause it to be skewed to one side. Again the drop-out alignment can be checked using the proper tool. Sorry to go on about "the proper tool", I'm aware that most cyclists don't have access to these and buying frame tools is expensive just for an occasional job.

    Be aware that the hanger may appear true but it can be out in various orientations and not just in a vertical plane. The usual symptoms of this is that it will change erratically going up perfectly for a few gears and then when changing down, dropping two at a time no matter the cable tension.
  • JimboPlob
    JimboPlob Posts: 397
    Does it need to be a track wheel then???
  • JimboPlob
    JimboPlob Posts: 397
    Took it to LBS. Mech hanger off by 10mm each way. The mechanic kindly said he would bend it back for free as best he could. Didn't want to push it too far he said because he was a little worried it would weaken it too much. Advised to buy a new hanger.

    At least its shifting much better now and I finally got to the bottom of it.

    Thanks all for your help.
  • andi1363
    andi1363 Posts: 350
    Had pretty much the same issue with a brand new Ultegra 10 set up. It was fine when new but after a few weeks, it got to the point of not indexing cleanly up or down. A tweak one way would make the other way worse.

    First off, it went back to the shop (50 mile round trip) and they just adjusted it and said bring it back if its no better. :roll: Not wanting to keep driving 50 miles just to be fobbed off, I decided to attempt to clear the fault myself.

    First I changed the cables. This sort of worked but after a few weeks it was back to square one..... Did this a few times before changing the cassette, chain, rear mech all to no avail! So I gave up and parked the bike.

    At work, I have a new colleague happened to be a mechanic in his previous job. So I asked him about this. Apparently its a well known issue with Shimano and an easy fix. He suggested changing the ferrels from plastic to aluminium and removing the in line cable adjuster. Did as He suggested along with yet another new cable inner and outer!

    The ferrules come as a pack of 4 and are less than a £5. Can't find any pictures but guess its these: http://www.madison.co.uk/productinfo.as ... f=6RT+9817

    edit found a pic: 49030.jpg

    Its only been 2 weeks but seems to have done the trick. I find I am changing gear far more often and spinning up hills instead of grinding. This is because I can now change gear and be 99% confident it will be fine! :D