FSA Gossamer retaining ring/lock nut issues

buder Posts: 154
edited July 2013 in Workshop
Hi All.

After reading numerous past threads and the FSA instructions I am still a little confused.

I have a FSA Gossamer BB386 compact and the retaining ring (10) below is not very tight/keeps coming loose.

I know this is required to back out the crank arm when undoing the main crank bolt but does the ring stop/keep the crank bolt tight, do I need to be concerned that its not exactly in there tight in that I can turn it out with my fingers if I wanted to ?.


  • pastey_boy
    pastey_boy Posts: 2,083
    When the crank bolt is done up tightly it does not touch the extractor cap (no10) but the cap still need to be tight as it will work loose and will be lost. You need a peg spanner to tighten it up, also a little bit of thread lock will help.
    Viner Salviati
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  • Monty Dog
    Monty Dog Posts: 20,614
    Definetly need Loctite on the retainer ring, I also put grease on the inside face of the washer, 9
    Make mine an Italian, with Campagnolo on the side..
  • keef66
    keef66 Posts: 13,123
    Could you not take it and the washer out and keep them somewhere safe till you need to remove the cranks?? Or does it perform some other secondary function?
  • buder
    buder Posts: 154
    Hi All,

    Thanks for the replies.

    Ive since purchased the park tools spa-2 pin wrench thing and applied some blue loctite I had lying around and it seems to have done the trick.

    My concern was as Keef mentioned below there was some kind of secondary function to the retaining ring that I wasn't aware of.

    My new bike had done 100 miles before the crank bolt needed tightening a quick google showed lots of similar complaints with the FSA Gossamer chainset. I notice FSA supplied the chainsets with some loctite 641 to help resolve the NDS arm walking off the splines, do I specifically need 641 or will my blue loctite be ok if this problems arises again ?.