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SLX Chainset Help!!!

MichaelMLFC92MichaelMLFC92 Posts: 401
edited April 2012 in MTB workshop & tech
Hello all, I bought an SLX double and bash chainset because it was cheap and intended on turning it into a triple setup. I purchased 44 and 32 tooth rings to replace the bashguard and 36 tooth ring. The 44 tooth ring fits fine but the middle one doesn't fit onto the sipder properly. There is a gap between the chainring and where it is meant to sit flush. I was wondering if anyone else has had this problem and if they know why an SLX chainring doesn't fit an SLX crank. I've looked it up and the crank arms are apparently the same for both the triple and double and bash setups.

Thanks for your help in advance,

Mike.

Posts

  • The RookieThe Rookie Posts: 27,747
    Some chainsets use different location diameters, use a Shimano one - like the one that came with your SLX in the first place..... You know of course that the double and bash crank/axle is heavier than triple.
  • .... There is a gap between the chainring and where it is meant to sit flush.....

    Check for an exploded view on the shimano europe website - technical support - tech docs. Click on the crank id and check that you have the proper 32 chainring.
    The SLX 32 chainring has 4 rounded bolt tabs that don't sit flush on the milled linear spider seats. There is about a 1mm gap. Torque your bolts properly and its like new from the factory.
    Post pics and crank and chainring order ID for us to be sure.
    The beefy 36 ring is actually from the Saint group but can be used for SLX and wherever else it fits and works as well.

    Matthew
    canadian. mechanic. GS1 and ProTour '04 & '05. church of bikes since 1978.
  • HortonHorton Posts: 327
    I've looked it up and the crank arms are apparently the same for both the triple and double and bash setups./quote]

    They're not exactly the same - the double and bash (FC-M665) are heavier duty and designed to be stronger & stiffer, whilst the triple (FC-M660) is more lightweight and XC oriented. The middle ring that comes with the M660 is composite/steel so I guess the bolt tabs might be a slightly different size than the 36T ring on the M665 but to be honest, I would have thought it's largely irrelevant as the BCD is exactly the same and that's the important thing. Since it's the chainring tabs that are slightly smaller than the milled bit on the spider the chainring can still fit flush with the spider so crank the bolts up nice and tight and it should be fine - I recently cobbled together some new & old parts and tried to fit a brand new deore 32T middle ring to an ancient STX RC (square taper...very old...) and although the BCD was the same, the bolt tabs on the new ring were bigger than the old crank so it would not fit flush (until I took a dremmel to the old crank to "fine tune" them...)
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