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Thread: FSA OEM Cranks

  1. #1
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    FSA OEM Cranks

    Anyone else use these? Read a blog earlier this year about someone dropping a crankarm in a race and thought how could that happen. I figured it must be older or beaten down. That was until one of my night laps at this past weekends Chico 24hr race. I was climbing a hil and felt as if my bearings blew in my left pedal. A few seconds later the foot hit the floor. luckily I was able to find the crankarm and bolt on the trail and do a "quick" rebuild with my toolkit. After hearing about the one incident and then having the same thing happen to my i figure it is time to let people know. Also I will be shopping soon I am sure for something else, any good reviews on competitive products would be appreciated. Thanks.
    Last edited by egggman; 06-28-2010 at 11:19 AM.

  2. #2
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    wth is NFA?

  3. #3
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    I dropped the NDS arm off my Spot on about the 3rd ride. Glad I was spinning along the pavement on the way to the trail, and not standing on the pedals stomping up a hill when it happened. FWIW, the crank was a Spot branded FSA. It went just like you described, the pedal went wonky, and I looked down right about when it fell off. I didn't find the bolt for mine - you were lucky to find yours.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

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    Quote Originally Posted by alexrex20
    wth is NFA?
    OOpse, NFA out FSA in, not sure why I typed the wrong one...

  5. #5
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    good reminder to keep checking the tightness of the bolts It can happen to any crank if the bolts loosen over time and you don't catch it

    The type of crank design least likely to have this problem is something like Shimano's external BB cranks that have pinch bolts perpendicular to the spindle on the non-drive side. The pinch bolts can be torqued tighter because they aren't setting preload or pushing the arm too far up a taper or anything.

  6. #6
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    Quote Originally Posted by boomn
    good reminder to keep checking the tightness of the bolts It can happen to any crank if the bolts loosen over time and you don't catch it

    The type of crank design least likely to have this problem is something like Shimano's external BB cranks that have pinch bolts perpendicular to the spindle on the non-drive side. The pinch bolts can be torqued tighter because they aren't setting preload or pushing the arm too far up a taper or anything.
    That's exactly the kind of design the FSA cranks have ... and that's what's falling apart here.

    I have a feeling that if that preload bolt falls out like mine did, the pedaling motion will work the crank arm right off the splines even if the pinch bolts are tight.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  7. #7
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    Quote Originally Posted by wv_bob
    That's exactly the kind of design the FSA cranks have ... and that's what's falling apart here.

    I have a feeling that if that preload bolt falls out like mine did, the pedaling motion will work the crank arm right off the splines even if the pinch bolts are tight.
    FSA makes a lot of cranks without pinch bolts now and I guess I assumed it was one of those. All their carbon cranks are a single bolt as well as their new BB30 stuff IIRC.

    Still very interesting as i've never heard of that problem before. I guess I need to get out more I remember being told on this forum that you should technically be able to remove that preload bolt without any problems, just like a top cap on a headset, as the pinch bolts should have more then enough force. Did you have blue threadlocker on the pinch bolts?

  8. #8
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    I didn't install the crank, it came on the bike, I think they had lock-tite on them but am not sure of that. For sure they do now - but the crank's laying on a shelf in the garage b/c 1x9 was not for me.

    This was a pretty common problem with the Spots, preload bolt falls out, crank arm falls off. Or, put another way, I wasn't the only person it happened to. I don't have a list or count handy, but there were other posts on the topic already on the forum when it happened to me. I just hadn't noticed them and taken actions to prevent it.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

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    I was talking to a bicycle manufacturer who uses these OEM cranks on the base model bikes. The same issue happened to him on his bike and he has dealt with many RMA's regarding this crank type. Complaints to FSA seem to do nothing apparently. Said again, this is second hand info.

  10. #10
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    FWIW, a little dobber of blue loctite and a extra 1/4 turn on the preload bolt after tightening the pinch bolts and this won't happen.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  11. #11
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    Yeah I was able to use mine once I got a new preload bolt and grade 8 pinch bolts (the heads rounded off in the originals). The cranks just didn't stick around on a bike long, with no provision for a granny gear (in my case).
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

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