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Gamut dual ring roller sticking

DodgeTDodgeT Posts: 2,255
edited January 2013 in MTB workshop & tech
Have a gamut chain device with the dual roller. It's forever sticking / jamming. I've had the bearing covers off a few times and re-greased, but a few minutes later its jammed again and the chain just glides over it instead of it turning.

Probably know the answer already, ie one of these http://www.chainreactioncycles.com/Models.aspx?ModelID=63923&utm_source=Google&utm_medium=Shopping&utm_name=UnitedKingdom , but just wondered if its possible to press out the old, and in with the new, sealed bearing. Or would it just be far easier to splash out the £15 ?

Posts

  • Are you not supposed to use oil rather than grease? I do and it runs fine.
  • DodgeTDodgeT Posts: 2,255
    It's the same type of bearing as used in wheel bearings, you grease those, so be fine. Think some censored had got in there before and buggered them up.
  • Dirtydog11Dirtydog11 Posts: 1,621
    I don't think you've got much to loose by trying to press the old ones out, what's the worst can happen?


    Ukbikestore has 608 2RS for £2.24

    http://www.ukbikestore.co.uk/product/14 ... rings.html
  • NorthwindNorthwind Posts: 14,675
    Is there not a wee pain-in-the-bum circlip in the Gamut roller?
    Uncompromising extremist
  • DodgeTDodgeT Posts: 2,255
    Cheers dirty. I did have a bash (literally) with a suitable sized socket, but didn't seem to do owt. I've brought it into work, where we have a proper press, so will have a try in a bit..

    North, yeah, has a small circlip on the outside, cant personally see what it does. I'm assuming that the pin through the unit must be seperate to the bearings, but its as solid as. Almost as if its one piece, which surely its not?

    Circlip was on the side in the bottom shot, so I guess it must screw out?

    IMG01627-20120123-1010.jpg

    IMG01626-20120123-1009.jpg
  • Dirtydog11Dirtydog11 Posts: 1,621
    Just had a look at mine and I can't figure out what that circlip does either.

    I'll be interested to know how this goes.
  • DodgeTDodgeT Posts: 2,255
    It stops the little bearing cover coming off if nothing else.

    Could do with an exploded view of the roller, similar to the shimano docs.

    Edit to add- just had a go at unscrewing the 2 pieces, they must unscrew, but they wont budge. (holding thread in vice then using allen key) Only thing I haven't tried is heating the part, but don't particularly want to do that.

    So, then tried to press the parts out. No chance, there must be a step on the inside of the roller, as the 2 bearings move laterally on each side, but will not move through. This also confirms that the thing should unscrew...

    Turns out, only one side is fubbarred. the outside turns lovely when you hold the outer shell. But the inside one jams when you hold the outer shell. Interstingly, it spins quite freely inside the roller though..
    So, gona grease her back up again and see how she goes.
  • DodgeTDodgeT Posts: 2,255
    Well, got home and I thought I'll try one last thing. Sat it in a tub of plusgas for an hour, spun it a few times back and forth, quite a bit of rusty censored come out and my balls are now clean and shiny and it runs peachy smooth :)

    I'd forgot just how good plusgas is.
  • 1mancity21mancity2 Posts: 2,355
    DodgeT wrote:
    Well, got home and I thought I'll try one last thing. Sat it in a tub of plusgas for an hour, spun it a few times back and forth, quite a bit of rusty censored come out and my balls are now clean and shiny and it runs peachy smooth :)

    I'd forgot just how good plusgas is.

    Or diesel, and get out of the small ring and use the big roller!!
    Finished, Check out my custom Giant Reign 2010
    Dirt Jumper Dmr Sidekick2
  • DodgeTDodgeT Posts: 2,255
    The nylon roller is one piece so don't make any diff. Be using the big ring sat :D
  • Dirtydog11Dirtydog11 Posts: 1,621
    Glad to see you got it working!
  • DodgeTDodgeT Posts: 2,255
    Well the roller has been cleaned / regreased a few times since this last post and I decided to have another look at it..
    It does come apart, you just need to give the central shaft a dam good whacking to get it out. (with circlip removed obviously)

    roller_zpsf9f20240.jpg

    So, nip across to simply bearings after work for 2 new bearings and she'll be good as new :) Prefer to pay £4 for a couple of bearings than £20 odd for the whole part.
  • Dirtydog11Dirtydog11 Posts: 1,621
    Thanks for the info, I'll probably go down this route once mine wear out.
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