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  1. #1
    Join Date
    Sep 2007
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    School me on cranks and BBs

    I have an older XTR M980 crank that I've been running as a 1x crank for a number of years and I think I'm going to replace it with a direct mount style crank. I'm currently looking at the Raceface Turbine 30 as it seems like it's relatively light and has a direct mount chainring - the latter of which will allow me to run smaller than 30t chainrings. I'm on a Hightower 1 with a 73mm threaded BB shell, and I'm pretty sure my current BB won't work (XTR SM-BB93) due to spindle size. Do I need the RF Cinch BSA30 or something else? I'm having a tough time understanding exactly what I need, as it seems like some external BBs don't play well with cranks intended for a PF BB.

    Any other cranks or BBs that I should consider that will allow for a smaller chainring (28t or 26t)? Price point is around $150-200 and I don't mind buying a used crank. I'd like to keep weight in the same ballpark as the M985 (~520g for the arms and spindle).

    Thanks!

    Seth

  2. #2
    Join Date
    Mar 2008
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    Aeffect
    Lee Lau - xxx-er is the laziest Asian canuck I know

  3. #3
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    Jan 2009
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    +1 for Aeffect. Have run them on several bikes. Just make sure you get the version with a self-extracting bolt. I somehow ended up with one that does not have the self-extracting bolt and having to bust out the crank puller when needed is kind of annoying. Weight is just under 600 grams for arms+spindle and I think you can keep rocking your XTR bb if you want. Oh and they are cheap so you can just go ahead and buy new.

  4. #4
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    Yes, Aeffect is 24mm.
    StokePimpin' ain't easy

  5. #5
    Join Date
    Dec 2007
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    Hell Track
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    What length are you looking for? I think I have some Raceface Sixc cranks that I could sell you that'd fit your budget. I'd just need to check and see what spindle and BB I have for them.

  6. #6
    Join Date
    Oct 2003
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    slc
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    10,892
    Quote Originally Posted by radam View Post
    Just make sure you get the version with a self-extracting bolt. I somehow ended up with one that does not have the self-extracting bolt and having to bust out the crank puller when needed is kind of annoying.
    You can buy the self-extracting bolt aftermarket for under $10.

  7. #7
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    Mar 2008
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    the ham
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    6,523
    While race face make great cranks, their bottom brackets aren't.

  8. #8
    Join Date
    Sep 2004
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    LV-426
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    X-whatever on the Aeffect -- 24mm spindle that will fit your existing Shimano BB.

    If your BB is worn out too, then perhaps consider a SRAM direct mount crank + BB.
    Quote Originally Posted by powder11 View Post
    if you have to resort to taking advice from the nitwits on this forum, then you're doomed.

  9. #9
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    Mar 2008
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    Quote Originally Posted by radam View Post
    Just make sure you get the version with a self-extracting bolt. I somehow ended up with one that does not have the self-extracting bolt and having to bust out the crank puller when needed is kind of annoying .
    Hold the bike up in the air by its cranks, tap on spindle end with a hammer & drift they came lose pretty easy
    Lee Lau - xxx-er is the laziest Asian canuck I know

  10. #10
    Join Date
    Apr 2008
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    Virgina (It's humid here)
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    Crank puller? Fuck that. What are you selling, square taper?

    Buy Toast's cranks. Maybe he's even got a BB for you.

    Other option is to get a Sram GXP X0 crankset for about $200 bucks and get a GXP threaded BB for another $30.
    If you want me to take a dump in a box and mark it tubeless, I will. I got spare time.

  11. #11
    Join Date
    Apr 2012
    Location
    Cascades
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    448
    On this subject, I have an old Surly Karate Monkey with a square-taper BB, 73mm BB shell (or whatever the MTB standard is), and a Shimano Hollowtech (II?) crankset. The BB was getting a bit clicky, which was cool because the click pitch + volume was proportional to torque on crank, so it was like getting a free power meter. On this morning's commute, however, I managed to destroy the chainring and crank spider in the middle of a busy intersection.

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    I have a number of spare parts, which are not compatible with each other:

    3x Race Face direct mount chainrings
    SRAM Rival crankset with 68mm spindle (or whatever; spindle not long enough for BB shell) and 40t chainring
    SRAM GXP BB (fits in BB shell, which is how I found out the crank spindle is too short)

    Is there a crankset I could buy that works with RaceFace direct mount rings AND GXP BB? Or should I buy a SRAM crankset + ring? Or what?

  12. #12
    Join Date
    Sep 2007
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    2,555
    Buy my old XTR m985 crank for cheap?

    Sent from my SM-N970U using Tapatalk

  13. #13
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    Quote Originally Posted by Toddball View Post
    Is there a crankset I could buy that works with RaceFace direct mount rings AND GXP BB? Or should I buy a SRAM crankset + ring? Or what?
    Probably cheapest to get a RaceFace Affect Cinch crankest and bottom bracket that will work with your chainrings. Or get a Sram X9 GXP crankeset and buy new chainrings. Just make sure you don't get a BB30 version.
    Edit: or buy that XTR for cheap. Those things are light as ballz.
    If you want me to take a dump in a box and mark it tubeless, I will. I got spare time.

  14. #14
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    Quote Originally Posted by Toddball View Post
    The BB was getting a bit clicky, which was cool because the click pitch + volume was proportional to torque on crank, so it was like getting a free power meter.
    No way to tell now but I am willing to bet it was a great power meter until it tore itself apart because the fasteners were loose
    Lee Lau - xxx-er is the laziest Asian canuck I know

  15. #15
    Join Date
    Oct 2002
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    Shadynasty's Jazz Club
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    Another Aeffect w/ Shimano BB vote.
    Remind me. We'll send him a red cap and a Speedo.

  16. #16
    Join Date
    Apr 2012
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    Cascades
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    Quote Originally Posted by XXX-er View Post
    No way to tell now but I am willing to bet it was a great power meter until it tore itself apart because the fasteners were loose
    I miss it already!

    Quote Originally Posted by bagtagley View Post
    Another Aeffect w/ Shimano BB vote.
    Ordered this combo, thanks.

  17. #17
    Join Date
    Sep 2018
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    1,156
    Quote Originally Posted by XXX-er View Post
    No way to tell now but I am willing to bet it was a great power meter until it tore itself apart because the fasteners were loose
    Has to be. The only way that happens is if one of the chainring bolts was super loose or popped off entirely.

  18. #18
    Join Date
    Sep 2007
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    Alright, here's my follow-up question. I'm picking up Toast's raceface Sixc crank and BB (thanks Toast!) tonight and need to pair it with the right chainring. I have a standard 68/73mm threaded BB shell on my Hightower v1 with a 50mm chainline. Do I need the chainring with 3mm or 6mm offset?

    Thanks in advance.

    Seth

    Sent from my SM-N970U using Tapatalk

  19. #19
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    Sep 2004
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    LV-426
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    Boost or non-boost frame?

    Edit to clarify: boost frame with boost-appropriate crank = 3mm.
    Non-boost frame with non-boost crank = 6mm.

    I don't know if there is a difference between boost and non-boost Race Face cranks. Being a direct mount chainring, I wouldn't think so, but...
    Quote Originally Posted by powder11 View Post
    if you have to resort to taking advice from the nitwits on this forum, then you're doomed.

  20. #20
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    Sep 2007
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    2,555
    Boost (148) rear end.

    Sent from my SM-N970U using Tapatalk

  21. #21
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    Quote Originally Posted by El Chupacabra View Post
    Boost or non-boost frame?

    Edit to clarify: boost frame with boost-appropriate crank = 3mm.
    Non-boost frame with non-boost crank = 6mm.

    I don't know if there is a difference between boost and non-boost Race Face cranks. Being a direct mount chainring, I wouldn't think so, but...
    I'd love the experts to chime in on this: My vague understanding is that there is zero difference between a Boost and a Non-Boost Crankset (assuming we stick to talking about spiderless chianrings). The difference is the offset of the chainring, which they sell with specific offsets fitting each of the spiderless mounts. I assume it would be a different story with spidered (ie Shimano and cheap) cranksets. But maybe I'm wrong. ............ Then there's Super-Boost/157Trail as well as good olde DH .......
    Please, someone, help us see the light!
    If you want me to take a dump in a box and mark it tubeless, I will. I got spare time.

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