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Shimano UN55 Bottom Bracket

USD$19.99 20% off USD$24.99 msrp
Item #: BB257F01
USD$19.99 20% off USD$24.99 msrp
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Shimano UN55 Bottom Bracket

High quality Shimano sealed bottom bracket (square taper). Extra strong Aluminum (not plastic) non drive cup. Please choose width and spindle length.

  • English Threaded
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REVIEW SNAPSHOT®

by PowerReviews
Shimano UN55 Bottom Bracket
 
4.6

(based on 36 reviews)

Ratings Distribution

  • 5 Stars

     

    (25)

  • 4 Stars

     

    (9)

  • 3 Stars

     

    (2)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

97%

of respondents would recommend this to a friend.

Pros

  • Easy to install (28)
  • Durable (18)
  • Enhances pedaling efficiency (13)
  • Lightweight (5)

Cons

No Cons

Best Uses

  • Mountain biking (16)
  • Road biking (16)
    • Reviewer Profile:
    • Avid cyclist (16), Casual/ recreational (8), Commuter (6)
    • Was this a gift?:
    • No (30)

Most Liked Positive Review

 

5 star rating

Bought this BB and so far it is a winner. Very smooth and more importantly, very strong. I put a lot of downward force on my pedals and this BB is stiff and...Read complete review

Bought this BB and so far it is a winner. Very smooth and more importantly, very strong. I put a lot of downward force on my pedals and this BB is stiff and strong. All my power goes to the wheels.

VS

Most Liked Negative Review

 

Minor problem: loose cap

I've bought 3 of these UN55 units, and on two of them the aluminum cap appears to be loose on the cartridge, by about .020". I made a plastic spacer to...Read complete review

I've bought 3 of these UN55 units, and on two of them the aluminum cap appears to be loose on the cartridge, by about .020". I made a plastic spacer to take up the play. On the third unit, the cap seems to fit neatly. Possibly these were packed with the wrong cap?

Reviewed by 36 customers

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Displaying reviews 1-10

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5.0

No fuss bottom bracket

By Cronometro

from Wausau, Wi

About Me Avid Cyclist

Verified Buyer

Pros

  • Durable
  • Easy To Install

Cons

    Best Uses

    • Road Biking

    Comments about Shimano UN55 Bottom Bracket:

    Almost indestructible bottom bracket. Inexpensive and long lasting.

    • Was this a gift?:
    • No
     
    5.0

    Works as intended

    By Gnorm

    from B.C. Canada

    About Me Casual/ Recreational

    Verified Buyer

    Pros

    • Durable
    • Easy To Install

    Cons

      Best Uses

      • Mountain Biking

      Comments about Shimano UN55 Bottom Bracket:

      Great.

      • Was this a gift?:
      • No
       
      5.0

      GREAT Bottom Bracket

      By Dr Tim

      from Northeast, TX

      About Me Avid Cyclist

      Verified Buyer

      Pros

      • Durable
      • Enhances Pedaling Efficiency

      Cons

        Best Uses

        • Mountain Biking
        • Road Biking

        Comments about Shimano UN55 Bottom Bracket:

        This is a great bottom bracket. I have ordered two of these now. The first one I put on my Mountain Bike. It now has over 1000 miles without any problems at all. The second one, I put on a bike that I am restoring.

        • Was this a gift?:
        • No
         
        5.0

        Great Replacement Bottom Bracket

        By Dr. Tim

        from North East, TX

        About Me Avid Cyclist

        Pros

        • Durable
        • Easy To Install
        • Enhances Pedaling Efficiency

        Cons

          Best Uses

          • Mountain Biking
          • Road Biking

          Comments about Shimano UN55 Bottom Bracket:

          The Shimano UN55 Bottom Bracket is an excellent replacement bottom bracket. I have uses the UN55 on several bikes that I've upgraded and restored. One of them I ride regularly and have over 800 miles on the UN55. I highly recommend this bottom bracket.

          • Was this a gift?:
          • No
           
          5.0

          Great upgrade for 1999 Trek 6500 MTB

          By ek

          from Ahia

          About Me Commuter

          Verified Buyer

          Pros

          • Aluminum Cup
          • Easy To Install
          • Enhances Pedaling Efficiency

          Cons

            Best Uses

            • Mountain Biking

            Comments about Shimano UN55 Bottom Bracket:

            With my limited bike knowledge, took some time scratching around to determine the UN55 was correct replacement.

            • Was this a gift?:
            • No

            (0 of 1 customers found this review helpful)

             
            4.0

            Solid part, very smooth!

            By Frazinator

            from Guelph Ontario

            About Me Avid Cyclist

            Verified Reviewer

            Pros

            • Easy To Install
            • Enhances Pedaling Efficiency

            Cons

              Best Uses

              • Road Biking

              Comments about Shimano UN55 Bottom Bracket:

              This is an awesome bottom bracket for fixed gear bicycles, I bought it to go with a pure-fix crank and they work well together (ie. Square taper). The only thing I would say negative about it, which applies mainly to track/fixed bikes. I had a friend who's chain snapped and in that process (including a bail) the bottom bracket bent a tiny amount, but was barely enough to notice while riding.

              • Was this a gift?:
              • No
               
              4.0

              Good product at good price

              By markw

              from Charleston, SC

              About Me Avid Cyclist

              Verified Buyer

              Pros

              • Easy To Install
              • Enhances Pedaling Efficiency

              Cons

                Best Uses

                  Comments about Shimano UN55 Bottom Bracket:

                  Bottom bracket on road bike finally wore out, this was easy to install and greatly improved peddling.

                  • Was this a gift?:
                  • No
                   
                  4.0

                  Execellent Easy to Install

                  By Dean

                  from Moberly, MO

                  About Me Casual/ Recreational

                  Verified Buyer

                  Pros

                  • Easy To Install

                  Cons

                    Best Uses

                      Comments about Shimano UN55 Bottom Bracket:

                      I used this to replace the cheap factory FSA that was a heavy steal consturciton, yet quickly (under 500 miles) developed a grating sound while cranking hard up hills. Though I am a heavier rider at 210lbs and am riding a low end bike that's just one step up from buying one off the shelf at Walmart. Installation was easy, only had to do a minor adjustment on the high and low stops of the front derailer as the offset was slightly different on the drivetrain side from the FSA bracket. Pedalling feels smoother after around 200 miles on the new bottom bracket than it ever did on this bike before. Happy so far with this product.

                      • Was this a gift?:
                      • No

                      (1 of 1 customers found this review helpful)

                       
                      4.0

                      Good fix to worn cup and spindle bb

                      By Gr1m

                      from Cape Cod ,MA

                      About Me Avid Cyclist

                      Verified Buyer

                      Pros

                      • Easy To Install
                      • Enhances Pedaling Efficiency

                      Cons

                        Best Uses

                        • Road Biking

                        Comments about Shimano UN55 Bottom Bracket:

                        I've used this bottom bracket a couple times to replace pitted and rusted spindles. Very easy installation and reliable. Although, I do like my RaceFace external bearing bb a little better.

                        • Was this a gift?:
                        • No

                        (1 of 1 customers found this review helpful)

                         
                        5.0

                        Easy to replace bottom bracket

                        By Gregg

                        from Olathe, KS

                        About Me Commuter

                        Verified Reviewer

                        Pros

                        • Easy To Install
                        • Enhances Pedaling Efficiency

                        Cons

                          Best Uses

                          • Road Biking

                          Comments about Shimano UN55 Bottom Bracket:

                          I was glad to be able to replace the bottom bracket on my own. Easy instructions.

                          • Was this a gift?:
                          • No

                          Displaying reviews 1-10

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                          Get free shipping with your $50 purchase today when you choose Standard Shipping at checkout. Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items

                           

                          Free Shipping Offer

                          Get free Standard Shipping with your $50 purchase today! Just choose Standard Shipping during checkout.

                          Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items.