2mm Spacer on Shimano 10sp Cassette

GavH
GavH Posts: 933
edited March 2009 in Workshop
Just removed my 10 speed 105 12-25 (CS-5600) and replaced it with a lightly used, 2nd hand Ultegra 12-27 (CS-6600). Fitted it no bother and the Ultegra is on and secure and shifting up and down ok and with no apparant play in it.

Problem / question I have is that the technical instructions on the Shimano site show a 2mm Spacer which sits between the lowest hear (biggest sprocket) and the wheel hub (Shimano WH-R550). Neither the Ultegra cassette I bought nor the 105 cassette already on the bike have one. Both tech instructions (linked below) show it for the 12-25/27 cassettes.

So what's it for? Am I missing one or does it not matter seen as my gears are shifting ok?

Sorry if this is a billy basic one!

http://bike.shimano.com/media/techdocs/content/cycle/SI/105/CS-5600/SI_1ZF0B_13_v1_m56577569830603681.PDF

http://bike.shimano.com/media/techdocs/ ... 611834.pdf

The part marked (A) on the diagrams.

Comments

  • Pokerface
    Pokerface Posts: 7,960
    Size of the freehub usually determines if you need the spacer or not. If your cassette is locked on the freehub nice and tight - then you're OK.
  • GavH
    GavH Posts: 933
    Thanks pokerface, I can assume therefore that if the cassette is working fine and has no play than it doesn't actually need the spacer ring.
  • Pokerface
    Pokerface Posts: 7,960
    In my experience it is VERY obvious when you need the spacer.


    I have two sets of Mavic wheels - one Cosmic and one R-Sys, both with Shimano freehub - and both running the exact same cassette - but one of them needs a spacer. Couldn't get the cassette even close to being tight without it.
  • lfcquin
    lfcquin Posts: 470
    Pokerface wrote:
    I have two sets of Mavic wheels - one Cosmic and one R-Sys, both with Shimano freehub - and both running the exact same cassette - but one of them needs a spacer. Couldn't get the cassette even close to being tight without it.

    As I found out a couple of weeks ago Mavic wheels need a larger (apprx 3mm) spacer with Shimano 10 speed cassettes. If this isn't fitted or the standard Shimano spacer is fitted then it rattles like crazy, but tends to still shift ok.

    Every Shimano 10 speed cassette I have bought have come with the spacer shown on the Spec pages GavH, the reason is that the 10 speed cassette is narrower than the 8/9 speed, I guess yours might be missing because it is 2nd hand. If you don't have any play when riding then I guess you are cool but it might just be worth mentioning to your IBD when you visit next just to be sure.
  • Pokerface
    Pokerface Posts: 7,960
    I should have mentioned that my cassettes are Sram Red.


    But I've used Dura Ace 10 speed cassettes in the past - and they all came with, and needed the spacer.
  • nicklouse
    nicklouse Posts: 50,675
    Pokerface wrote:
    I should have mentioned that my cassettes are Sram Red.


    But I've used Dura Ace 10 speed cassettes in the past - and they all came with, and needed the spacer.

    so for the 10spd there should have been a spacer and for the 9spd there should not be one.

    Is it still pressed up on the 10spd cassette?

    the body width is the same for 8/9/10 (except for the 10 only but that has deeper splines)
    8/9 cassettes are the same width and the 10 is wider but the base is narrower and needs a spacer, (there is a step lifting the big cog over the join between the body and the hub)
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
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