Shimano Dura Ace 7900 C24 wheelset - Cone adjustment

chris217
chris217 Posts: 217
edited April 2011 in Workshop
Ok identified loose cones, quite a bit of play in rear and a little in the front.

aware this is a cup / cone system but can anyone point me to exact instructions as to how to tighten as i cant find anything .

bit limited in bike maintanence !!!

cheers

Comments

  • tonye_n
    tonye_n Posts: 832
    DesWeller wrote:
    +1 I used this for adjusting my DA 7850 sl wheelset.
    The instructions should work for all cup and cone hubs... i.e. shimano
  • Simon G
    Simon G Posts: 41
    Chris217,

    I did this exact job yesterday. You'll need two 5mm allen keys (although you may be able to get away with just the one) and a 17mm cone spanner.

    The Park tools link is definitely a really good starting place, but there's nothing like knowing the exact method for your specific wheelset is there. Park will give you a good idea of what you are actually trying to acheive - which bits you are adjusting and so on.

    1. Take your skewer out of the wheel and concentrate on the non-drive side of the wheel. You'll notice that you can fit a 17mm cone spanner on the 'flat sided washer / nut' (on my wheel this is coloured black). Once you've got the cone spanner in place, stick your 5mm allen key down the centre of the axle (same side as the cone spanner). You're effectively putting the allen key into the same place from where you've just removed your skewer, but there is actually a 5mm hex fitting in there too! Hold the cone spanner firm and rotate the 5mm allen key counter-clockwise to loosen it slightly. You are now undoing the bolt which locks the cone into it's current position!

    2. Now for the fiddly bit - If you stick your spare 5mm allen key in the driveside allen fitting, you can then use your cone spanner to tighten the cone clockwise (non-driveside) whilst holding the axle still with the 5mm allen key (driveside). Tighten until there is no play in the axle, but the bearings can still run freely (this can be quite a fine adjustment) - play around a little by loosening and tightening to get a feel for what you are actually doing here.

    3. Still fiddly - with your cone spanner in place, lock the cone into its new position by tightening the non-driveside allen key (clockwise) onto the cone. This can be fiddly because you may find that despite your best efforts to keep the cone in its 'perfect position', you actually tighten or loosen it slightly when nipping up the lock nut! You'll see what I mean when you get there - The job can be a three handed monster, so if you get it wrong just undo and start again!

    Good luck - hope this helps.
    Simon G
  • chris217
    chris217 Posts: 217
    Many thanks all, problem bit more than cones .... unfortunately appears axle loose and had to involve shimano mechanic who has completely stripped hub and tightened cones, play is still considerable.

    wheel now on way back to Madison .. will keep informed
  • desweller
    desweller Posts: 5,175
    Loose freehub body then?
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  • Simon G
    Simon G Posts: 41
    Good luck with madison - I'm sure that they'll be suportive and will sort the problem out for you.

    It sounds like a very odd problem. There's really not an awful lot going on inside the rear hub. The Freehub body is attached to the hub with a big old thread and if that was loose, you wouldn't have any play in the axle. Perhaps the hub itself has collapsed in some way (e.g. the recess which holds the cups has started to disintigrate?)

    At least you've learned a thing or two about the internals of shimano hub!

    Let us know how you get on.
    Simon G