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  1. #1
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    Rock Shox SID Brain 29 Fork Crown Race?

    Just got a 2012 Rock Shox SID Brain 29 fork and I will be putting it on my 2012 S-Works Epic 29 frame. Does this fork require a crown race or is the race built in to the carbon steerer? The specialized chart is unclear to me. There is no visible built in race on the steerer like some of the older Specialized forks that have that feature.

  2. #2
    The Other Dude
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    The new one does not have the crown race built in like previous models, you just drop your 1.5 lower crown race onto the fork. Enjoy, that fork rocks!
    Sponsors: Specialized, Honey Stinger, The Hive, Twenty6, 661, Elka Suspension, www.Chainsmokeracing.net

  3. #3
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    Hello, I'm new to the forum.

    I have a similar question. I purchased a complete S-Works Epic 29er 2012 SRAM last September. Since it was an early purchase, it came with a pre-release fork with aluminium steer tube. The bottom of the steer tube ended up flat, and the assembly had a bottom crown race tapered 45deg, a bearing tapered 45deg.

    Now Specialized replaced the top part of fork with the all carbon steer-tube. According to the manual, it should be a "built in crown race" which does not require a 1.5'' crown race (which was used on the aluminium steer tube).

    On the manual, the "built in crown race" is shown to be tapered 45deg, to match the bearing taper, but in reality the fork I got has a carbon steerer with a bottom race which ends flat. My question is, do I use the 1.5'' crown race from the alu fork or not?
    Attached Thumbnails Attached Thumbnails Rock Shox SID Brain 29 Fork Crown Race?-dsc_4659.jpg  

    Rock Shox SID Brain 29 Fork Crown Race?-dsc_4660.jpg  

    Rock Shox SID Brain 29 Fork Crown Race?-dsc_4661.jpg  

    Rock Shox SID Brain 29 Fork Crown Race?-dsc_4662.jpg  

    Rock Shox SID Brain 29 Fork Crown Race?-dsc_4663.jpg  


  4. #4
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    The specialized literature is confusing. Interested to hear what others did.

  5. #5
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    Thinking logically, I'd say I should use the crown race as I need to center the bearing. Forgot to say that the bearing on the carbon steer tube without crown race has radial free play, meaning it's not a feasible solution.

    Without Specialized manuals, I'd say I need to use the crown race.

    Any possibility that a carbon tube does not like a cut crown race, which will actually squeeze the tube and maybe dent it in the zone of the cut on the race?

  6. #6
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    You need the crown race.

  7. #7
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    Specialized sent me a race but it is not a split but rather the solid version. It went on quite tightly, like hammer tight.....

  8. #8
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    Thank you guys for your help. I'm confused as well because the shop where I bought the bike says don't use the split race, but it does not feel right.

    @CHSAD: that's interesting. Did your fork come with the black flat race like mine, and then Specialized sent you an extra race (solid) which was hammer fit? Could you post a pic (even mounted on the bike is fine)?

    @briscoelab: so far that seems the reasonable solution. But as I said, maybe split races are NG for carbon, and it would make sense since CHSAD got a non-split race from Specialized.

  9. #9
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    mrciave-bike is @ shop picking up next week. I will post a pic. My fork came in a box w/no hardware. Had to source the headset/compression plug from specialized. No crown race was sent at first but when questioned a solid crown race was sent and it is black. Also fork did not come with the giant black o-ring that goes on the crown. A call to them resulted in "call SRAM, it's their fork" or "hit and autoparts store". A trip to the autoparts store produced an o-ring but it is not as big as the one that comes on the complete bike. Specialized also did not know what size o-ring for me to get.

  10. #10
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    That's crazy!!! You buy a Brain fork (which is obviously a Specialized custom item), to fit on a Specialized bike, and they tell you "call SRAM"?????

    I thought buying Specialized guaranteed a great customer service but between your issue and my issue I might have to reconsider.

    Anyway, just to confirm:
    - At first your fork had no crown race, so no metal part, just the carbon?
    - When you got the black race, was same shape as my black one or was it tapered at the end?

    By the way, no big O-Ring for me as well, neither on the aluminium nor the carbon one...

  11. #11
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    Yeah, I was a little taken a back by my phone call. Now I know that sometimes when you get different people you get different answers. But that said the fork did come directly from specialized to my shop. I did not bother calling SRAM because they are notorious from not talking to non-shop employees.
    The race looked very similiar to one you have but when I slid it on the steerer tube it went 3/4 of the way down and stopped which I thought was weird. I have installed crown races on FOX forks and they have been the split variety which just dropped right on, same with a tapered REBA that I had on another Epic 29. Wondering if they sent the correct race.

  12. #12
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    Well, let's see if other forum users can contribute with extra info.

    So far I'm convinced to mount with the split crown race.

  13. #13
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    i got a complete bike from speci. 2012 and it comes with split crown race mounted !

  14. #14
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    Sounds like split crown race it is. I wonder then if my non-split should come off?

  15. #15
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    Hello Gronkjaer,

    do you have the S-Works bike, with carbon fork? So same configuration as mine, black collar ending flat plus split crown race tapered?

    If so, it clears everything. By the way, do you have the O-ring?

  16. #16
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    If the non-split ring has the right taper on it for the inside bearing shoulder, then there is no reason to remove it. I'm not sure which mine has installed, I can't remember from when I built it up.

    I personally think the non-split ring type hold the bearing preload better over time... but have used both on various bikes over the years.

  17. #17
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    Well, I'll have to do with the split one. Anyway there's a split one also on the top bearing, meaning that carbon can accept it.

    I'll build the bike and ride it over the weekend, let's see.

    Thanks a lot for the help.

  18. #18
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    This thread has been really helpful. Glad I was not the only one confused by the Specialized literature and crickets on their end....should be a bit more simple then that, just installing a fork. Thanks for all the posts.

  19. #19
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    Briscoelab, if you look at the steer from the bottom of the bike, it should be possible to see what kind of configuration you have. Maybe you just need to slightly move the O-ring (if present)...

  20. #20
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    mrciave, did your race just drop on or did you have to force it onto the fork?

  21. #21
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    The black "collar" (not sure how to call it) seen in this picture came with the fork, and I guess it's interference fit (does not come off).



    The split crown race goes in just dropping.

  22. #22
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    Right, but when you put your split crown race on the fork as you show in another picture did it just "drop on" are did you have to force it all the way on?

  23. #23
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    The split race is actually loose, but when you install the tapered bearing it will compress it and make it tight on the steer tube.

  24. #24
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    Fork installed WITH split crown and 50km on it, so far so good.

    In a couple of hundred kms I'll take it down to inspect, but I guess it's OK.

    Great help from everybody!

  25. #25
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    I sources a split crown. Hoping to have mine all set by next week...

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