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Details

  • Sealed cartridge bearings ensure lasting, smooth-spinning performance
  • Fits English-threaded 68mm bottom bracket shells; available in various spindle lengths (select from size drop-down list)
  • Crank arms must be square taper JIS-compatible

Imported.

  • Save 10%! This item qualifies for our drivetrain bike part discount. See Details

View all Shimano Bike Bottom Brackets

REI membership

Specs

Best Use Mountain Biking
Material(s) Chromoly
Weight 320 grams
Rated 5 out of 5 by from Nice price - easy install - smooth ride Nice upgrade for my bike, sealed bearings are so much quieter. Very easy to install, but of course bottom bracket tool required (Park Tool Sealed Bottom Bracket Tool - BBT-22).
Date published: 2016-07-09
Rated 5 out of 5 by from Solid UN53 replacement My son's touring bike (Surley Long Haul Trucker) was in a bike-car accident where the frame and back wheel were bent. The old bottom bracket, a UN53, had a cracked sleeve nut because it was made of plastic, otherwise it was fine. This new one has a reasonable cost, fits exactly the same as the UN53, and the sleeve nut is aluminum instead of plastic. It is working fine and should last a long time.
Date published: 2013-07-27
Rated 4 out of 5 by from Solid BB with a few problems I bought this UN55, 68x110, to replace a Sunlite BB. I've ridden with these before and they worked fine but the one I purchased had a few problems. After putting decent mileage on it, it still felt like it hadn't broken in and it was making a lot of noises. As far as I can tell they were torque creaks but it was annoying still. Installation seemed fine but even with lightly greased threads it was tough getting the drive side dialed in. I removed it recently, cleaned it and found that there was some type of anti-seize/PTFE on the threads which had solidified, probably causing the rough install. My BB shell and its threads are perfect so I have to say it was this particular BB. This doesn't mean this line of BB's are to be avoided, I just had problems with this particular one. In hand it is hard to turn, even after riding it for a few months. Yes, I know moving it by hand and by leg power is completely different but there is hardly any give. Still recommend it, so I guess I would say just check the threads for whatever substance I found on mine and hope yours breaks in.
Date published: 2016-07-02
Rated 5 out of 5 by from cheap and fits the bill! REI had this in stock, quite convenient, works as it should
Date published: 2017-07-17
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Please select a color/size.

Reviews

Rated 5 out of 5 by from Nice price - easy install - smooth ride Nice upgrade for my bike, sealed bearings are so much quieter. Very easy to install, but of course bottom bracket tool required (Park Tool Sealed Bottom Bracket Tool - BBT-22).
Date published: 2016-07-09
Rated 5 out of 5 by from Solid UN53 replacement My son's touring bike (Surley Long Haul Trucker) was in a bike-car accident where the frame and back wheel were bent. The old bottom bracket, a UN53, had a cracked sleeve nut because it was made of plastic, otherwise it was fine. This new one has a reasonable cost, fits exactly the same as the UN53, and the sleeve nut is aluminum instead of plastic. It is working fine and should last a long time.
Date published: 2013-07-27
Rated 4 out of 5 by from Solid BB with a few problems I bought this UN55, 68x110, to replace a Sunlite BB. I've ridden with these before and they worked fine but the one I purchased had a few problems. After putting decent mileage on it, it still felt like it hadn't broken in and it was making a lot of noises. As far as I can tell they were torque creaks but it was annoying still. Installation seemed fine but even with lightly greased threads it was tough getting the drive side dialed in. I removed it recently, cleaned it and found that there was some type of anti-seize/PTFE on the threads which had solidified, probably causing the rough install. My BB shell and its threads are perfect so I have to say it was this particular BB. This doesn't mean this line of BB's are to be avoided, I just had problems with this particular one. In hand it is hard to turn, even after riding it for a few months. Yes, I know moving it by hand and by leg power is completely different but there is hardly any give. Still recommend it, so I guess I would say just check the threads for whatever substance I found on mine and hope yours breaks in.
Date published: 2016-07-02
Rated 5 out of 5 by from cheap and fits the bill! REI had this in stock, quite convenient, works as it should
Date published: 2017-07-17
  • y_2017, m_7, d_25, h_12
  • bvseo_bulk, prod_bvrr, vn_bulk_1.0.0-hotfix-1
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_4
  • loc_en_US, sid_830208, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_rei-inc
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getReviews, 40ms
  • REVIEWS, PRODUCT

Questions & Answers

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