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Shimano XTR SM-BB93 Bottom Bracket

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sale $34.99 $40.99

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    • Black, English
      sale $34.99

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    Stands for top-of-the-line.

    In the world of Shimano, the letters XTR stand for the best of the best. The English-threaded M-BB93 bottom Bracket is exactly that. It’s tough, extremely lightweight, and sealed to keep out dirt in the worst riding conditions imaginable. The M-BB93 fits 24mm crank spindles and is compatible with both 68mm and 73mm bottom bracket shells.

    • Tough, lightweight
    • Fits 24mm spindles
    • Compatible with 68mm and 73mm BB shells
    • Item #SHI000Z

    aluminum, steel
    Shell Width
    68 mm 73 mm
    Axle Type
    Recommended Use

    Tech Specs

    What do you think about this product?


    >Rating: 5

    Good product, cheap price

    I've put it through the wringer

    I have been through a couple BB on this bike and just upgraded to the XTR after my XT got really rough after a couple years. These things work and they are cheap, not too much more needed.

    >Rating: 5


    I've used it several times

    Threaded bottom brackets are the best! Easy to install and aren't notorious for creaking. Shimano XTR BB is light and durable. Cranks spin freely.

    >Rating: 5

    An excellent BB

    Smaller and lighter than the older design

    >Rating: 5

    No squeaks or creaks

    The BB is key in transferring wattage to the wheel, don't skimp.

    >Rating: 5

    The Best is in Reach.

    I've put it through the wringer

    Shimano bottom brackets install easily, hold up well, and don't cost a ton of money. Replace as needed to keep the cranks spinning smooth!

    >Rating: 4

    Good so far

    I've used it several times

    I upgraded from XT since these were on sale. I can't tell a noticeable difference in performance, so at this point I wouldn't pay any extra for XTR.


    BB Tool Adaptor

    Easy to use and install.


    BB Installation Tool Adaptor

    The bottom bracket comes with an adaptor to fit the cups for installation. It slides right into a Shimano bb tool and then onto the bb cup.


    BB93 Cup Size

    Here is a photo showing the smaller size difference between the BB93 and the previous iteration of the XTR bottom bracket that worked with the M980/M985 crankset.

    >Rating: 4

    Smaller cups than XT

    I've used it once or twice and have initial impressions

    Don't freak out when this arrives thinking it's the wrong size. The cups are much smaller and it comes with an adapter for your normal BB tool for installation. It just covers the BB opening in the frame.


    Will this work on my 2014 Salsa El Mariachi SS? Specs say 73mm bsa threaded bottom bracket.


    Hello, Will this work for my Surly cross-check? It has 68mm bb, English thread, and tapered square shaft.


    Will this work on my 2015 Santa Cruz Bronson (aluminum)? I will be upgrading my crankset to a Shimano XT 8000, 30T, 170mm crankarm.

    Hi Emily, Yes, this will work with that set-up.


    Does it comes with the TL-FC32 tool?

    HI Gerson, This bottom bracket does not include an installation tool. We have a good selection of both socket and wrench-style external bottom bracket tools. Give us a call or chat in to place your order, and we will get you the right tool!


    Does it fit a Shimano XT FCM780 Crankset?

    Hi Gerson,, This Shimano bottom Bracket will work with all Shimano Hollowtech cranksets, including the Shimano XT FCM780 crankset.


    Thanks, Rico! I'm looking for the most...

    Thanks, Rico! I'm looking for the most durable bottom bracket for my bike, which has the Shimano M542 crankset. Are there more reliable (better) bottom brackets that you would recommend?

    Well it depends on the money you want to spend, I would say the Chris King is the most reliable BB we stock at this point. I have put those on a lot of endure and DH bikes with no problems. I have seen the SRAM BB's blow out on Enduro and DH bikes from very avid endure DH riders. You have to consider how many times you have broken your BB if you break it a lot it will even out because you will be buying it twice as much. Spending more now could save in the long run. I hope this answers your question if you want to talk more about it email me directly at ececala@backountry.com


    Will this fit a Shimano M542 crankset?

    Will this fit a Shimano M542 crankset?

    Conrad, The answer is yes those cranks have a 24mm axle diameter which this BB excepts. Let me know if you have anymore questions, at ececala@backcountry.com Thanks, Enrico