FSA Gossamer crankset (BB6200)

paulbnix
paulbnix Posts: 631
edited May 2014 in Workshop
I acquired one of these new style FSA cranksets in the Planet X sale.
I've now got round to fitting it and have found an issue.
The NDS crank is attached via a central allen key bolt and this is tightened up to about 40 nm with a wavy spring taking up any slack.
The bolt becomes very tight long before the wavy spring starts to compress.
Anyone else fitted one of these?

Comments

  • Monty Dog
    Monty Dog Posts: 20,614
    Check that your BB shell is within tolerance - info in the BB fitting instructions. Provided there's no axial movement of the cranks when pulled/pushed then you should have little to worry about.
    Make mine an Italian, with Campagnolo on the side..
  • StillGoing
    StillGoing Posts: 5,211
    Fitted one for someone, torqued to the 38-41nm as recommended only for the NDS arm to come off during a ride only weeks later. FSA previously provided some form of thread locking to safeguard against it but I'm not sure I'd want something like that on my chain set.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • pirnie
    pirnie Posts: 242
    I've had a couple of SL-K chainsets (which essentially use the same attachment mechanism). The wavy spring isn't meant to compress all the way flat, it's there to keep the sideways preload on the bearing so what you're describing sounds fine to me. There are videos showing it on the FSA website ( http://www.fullspeedahead.tv/ )

    I've never had a problem with the crank arms loosening either (although I have seen it reported elsewhere too so I keep an eye on mine)
  • simonj
    simonj Posts: 346
    The SL-K's also come with 3 x grey rubber/plastic shims, which can be used to adjust the slack as required. May be the same with your crank. I think on mine I googled it and ended up fitting one of these grey thin rings between the BB30 seal and the wavy washer on the NDS, although they must supply 3 for some reason and more may be required in some instances.
  • simonj
    simonj Posts: 346
    Like this, in his fingers he has the wavey washer and a grey shim / spacer, there is also another on on the crank next to the bearing seal / cover :-

    1299594818048-15ztkfky1g14n-500-70.jpg
  • darkhairedlord
    darkhairedlord Posts: 7,180
    simonj wrote:
    Like this, in his fingers he has the wavey washer and a grey shim / spacer, there is also another on on the crank next to the bearing seal / cover :-

    1299594818048-15ztkfky1g14n-500-70.jpg

    the gossamer with the bb6200 isn't bb30, it's BSA!
    I have one from Planet - X but still not yet fitted, perhaps next year :roll:
  • paulbnix
    paulbnix Posts: 631
    Thanks pirnie the video showed the NDS and wavy washer looking just like it does on my bike.
    I just need an 8mm hex bit for my torque wrench and I'll be sorted.
    I think for peace of mind I'll add some locktite and carry an 8mm allen key with me until I'm happy.
  • paulbnix
    paulbnix Posts: 631
    I have borrowed an 8mm hex bit only to find that my torque wrench only goes to 24 nm.

    Once I have tightened to 24 nm how many clicks will it take to reach 41? - joking honest :D

    Seriously though I have taken it to 24 nm and then tightened a bit more. The wavy washer is still wavy so I think thats the best I can do without tripping down the LBS everytime I want to tighten the BB.
  • simonj
    simonj Posts: 346
    Yes if you like your own bike DIY you'll ideally need two torque wrenches, one for the 4-12nm bolts and a big one for crank and cassette duties.

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