Dura Ace 7850 wheel Hub Axle unit

Rchv Posts: 3
edited February 2015 in Workshop
My Shimano WH 7850 SL rear wheel hub was not running smoothly. I took it apart, and can see that the surface of the bearing cup on the axle is a little rough.

So I need to replace it, however I found out the part (Y3D198030) is closed by Shimano. It is number 5 part in this pdf: http://bike.shimano.com/media/techdocs/ ... 688501.pdf

Does anyone have the part for sale, or knows where to obtain it?


  • ugo.santalucia
    ugo.santalucia Posts: 28,301
    Pretty sure 7850 and 7900 are the same thing...
    left the forum March 2023
  • cycleclinic
    cycleclinic Posts: 6,865
    Any shop with a madison account can order them. Quite expensive though.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • Rchv
    Rchv Posts: 3
    @ugo.santalucia there's a difference in the axle, maybe the cup would fit but mine seems fixed to the axle.

    @thecycleclinic I checked teh Madison site, the part they have is for another 7850 wheel, the code of the part is different. The wheel I have is a 7850 SL

    thanks for the help by the way.
  • keef66
    keef66 Posts: 13,123
    Just to help you in your search, the thing you're looking for isn't a cup but a cone, in your case it appears attached to the axle.
  • mamba80
    mamba80 Posts: 5,032
    they may or may not have this in stock? or it might be for a different 7850 :(
    some of the german websites have shimano spares that Madison no longer or never have kept.
    fwiw, dependant on the wear on the rim braking surface, you might consider just cleaning up the cone with v fine wet and dry and reassemble with new grease an bearings? chances are the hub bearing cup is also worn, if the cone is on its way out.

    http://www.singletrackbikes.co.uk/m7b22 ... wgodSowArQ
  • cycleclinic
    cycleclinic Posts: 6,865
    No 7850 part in stock with madsion and they will never have them again. I have a wheel in the shop with a worn cone, none of the 7900 parts fit so this wheel has limited mileage left in it. such a shame so if you are reading keep these thing serviced regularly as the hubs can always be rebuilt onto custom drilled rims (carbon with alloy brake track) when the original rims wear out.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • Bump for an old thread. I respaced a 7850 hub to 135mm with a m770 rear axle (available at low cost at SJS), 775, 785, any 14mm Shimano axle will work just fine. Cut 5mm off and you have a 7850 axle. The drive side cone assembly is identical.

    http://www.sjscycles.co.uk/shimano-deor ... 6/?geoc=us