Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation: meanbeaver's Avatar
    Join Date
    Nov 2009
    Posts
    18

    Cassette lockring

    I have a Sram pg-990 cassette (11-34T) and lost the original lockring for it. I was able to buy a Token Lockring (shimano/sram compatible 11T) recently and installed it onto the cassette.

    It tightened up fine and holds the cassette correctly on the freehub however when I tightened it on there were no ''clicks'' that you usually hear when tightening a lockring.

    Is this ok? Perhaps some brands of lockrings click and some just silently screw on?
    Attached Images Attached Images  

  2. #2
    Mantis, Paramount, Campy
    Reputation: Shayne's Avatar
    Join Date
    Jan 2004
    Posts
    4,320
    Quote Originally Posted by meanbeaver
    Is this ok? Perhaps some brands of lockrings click and some just silently screw on?
    Should be fine. Some lock rings are serrated on the underside. That clicking is the grooves on the lockring falling in and out of the grooves on the 11T cog.
    Some lock rings are smooth on the back side and therefore won't 'click' when tightened.
    *** --- *** --- ***

  3. #3
    mtbr member
    Reputation:
    Join Date
    Nov 2008
    Posts
    1,496
    +1 it's the difference between serrated and non-serrated rings, either work fine if torqued to spec.
    fb
    www.chain-L.com

    The key to solving any problem is to understand and address the underlying cause.

  4. #4
    Old goat
    Reputation:
    Join Date
    Aug 2009
    Posts
    138
    fwiw- I just installed my new 990 cassette with the stock lock ring and didn't hear any clicks upon proper torque. maybe this old goat has gone deaf though. /shrug

  5. #5
    mtbr member
    Reputation: meanbeaver's Avatar
    Join Date
    Nov 2009
    Posts
    18
    Thanks folks. My guess is that the sram 990 lockrings and the Token after market lockrings are non-serrated so they don't click as some have mentioned above.
    I took the bike out for a long ride today and had no problems with the lockring coming lose or the cassette moving around.
    Strange though that my old 950 cassette w/lockring does click when tightening. You'd think Sram would make all there lockrings all the same?

  6. #6
    mtbr member
    Reputation:
    Join Date
    Nov 2004
    Posts
    423
    SRAM did make them all the same.... on the 990 11-34 9spd.
    The 8spds are spaced different so it needs to be different.
    The XX is spaced different so it needs to be different.
    The 970s and 980s are probably slightly different because of the carriage differences.
    XTR is different from XT.
    Chris King is different from Campy.

    I wonder if the "click" is from a notch(es) on the wafer thin washer some rings.
    I've only once in my life heard of a lock-ring coming loose. Kevin admitted he forgot to tighten it after snugging it up by hand.

  7. #7
    mtbr member
    Reputation: meanbeaver's Avatar
    Join Date
    Nov 2009
    Posts
    18
    I am talking about all Sram 9spd cassettes.

    There doesn't seem to be any reason why there should be a difference between PG-950, 970, 980, or 990 lockrings. All those cassettes have the same dimensions. A 950 lockring WILL fit on a 990 cassette and vise versa, so why have some lockrings serrated and others not? Doesn't really make sense.

    The "click" IS from serrated notches on the underside of the lockring which some have and others don't.

    The question now is why does Sram produce both types (serrated and non-serrated) when either one will work work fine on it's own?

  8. #8
    mtbr member
    Reputation:
    Join Date
    Nov 2004
    Posts
    423
    The notch i'm referring to in on a different axis and is on the wafer-thin washer, not the lock-ring.
    The wafer notches click on the lockring threads as the ring is turned.

  9. #9
    mtbr member
    Reputation: meanbeaver's Avatar
    Join Date
    Nov 2009
    Posts
    18
    That does not make sense and is not what this topic is about.

    There should be no washer between lockring and and smallest cog on the cassettte. If there is your doing something wrong.

    The underside of some lockrings are serrated (notches) they will click with the notches on the smallest cog when the lockring is turned (tightened or loosened).

  10. #10
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    199
    You guys just made me go look at 5 lockrings I have around here.

    Neither of the Srams have the wafer washer.....all of the Shimanos do, and every one I've ever used has had it (one of these is from an 8spd XT cassette from 2002 or so). All of the lockrings themselves are serrated. Both spec the same 40nm installation torque. (These are all 11T lockrings I'm looking at.) I'm really not sure why Shimano uses that washer but they're smooth before installation, whereupon they become permanently serrated to match the lockring. Looking at the Sram rings, they all show wear/rounding on the serrations from use. Maybe the wafer washer on the Shimano provides a buffer for repeated installation and removal? The serrations on the old Shimanos look no different to me than the what's on the new, unused one.

    The serrations are to help prevent loosening from vibration during the ride....if you notice, they're a bear to remove sometimes, requiring considerably more torque to loosen than what they were installed with. Safety measure, I'm sure, just in case someone put one on loosely. And it might even be a throwback preventative from the days when freewheel cogs had 2 or 3 that threaded on to hold it all together (no lockrings in those days except for track hubs)....if you didn't get the first two cogs screwed tight with a chain whip, they could tighten during riding and effectively cause the last one to come loose. Made a nice tinkling noise until your chain got jammed in the crack and your seatstay got all gouged to hell. Industries can hold on to tradition sometimes. With today's hubs, even if the lockring comes loose there isn't enough space for the chain to jam or for the small cog to back off more than a couple mm's. Probably would just get some skipping when the chain was on the loose cogs.


    A non-serrated lockring should stay put just fine if you tighten it properly. I guess it's possible that it could vibrate loose, so maybe those types would be good to check for tightness every so often.


    I guess that doesn't answer your question as to why they'd make a non-serrated one. My only thought there is that it's a "compatible" part from another manufacturer, and in this case "compatible" refers to the cassette spline pattern (Campy vs. Shimano/Sram) and respective stack widths of the cassettes/carriers.
    Last edited by Crankenator; 03-12-2010 at 03:02 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •