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Shimano BB-UN26 Square taper Bottom Bracket

4.4 out of 5 stars 137 customer reviews
| 31 answered questions

Price: $8.24 - $59.99
Sale: Lower price available on select options
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  • Square taper interface
  • Sealed no service bearings
  • Plastic left cup
  • Shimano Reference Number: BB-UN26

Product Description

Shimano UN26 bottom bracket features a plastic left hand cup. Sealed bearings and high quality spindle make it last for years and it's maintenance free.

Product Details

  • Shipping Weight: 1 pounds (View shipping rates and policies)
  • Domestic Shipping: Item can be shipped within U.S.
  • International Shipping: This item is not eligible for international shipping. Learn More
  • ASIN: B007FP6NB8
  • Item model number: STPB-P
  • Average Customer Review: 4.4 out of 5 stars  See all reviews (137 customer reviews)
  • Amazon Best Sellers Rank: #11,588 in Sports & Outdoors (See Top 100 in Sports & Outdoors)
  • Product Warranty: For warranty information about this product, please click here

Customer Questions & Answers

Customer Reviews

Top Customer Reviews

Size: 68 x 117.5 Verified Purchase
This bottom bracket is very smooth and reasonably solid. It is a very good replacement for the loose bearings and cups normally fitted in less expensive bicycles. I recommend it specifically for an inexpensive rebuild of a nice older frame -- you know the one, you like it, it fits well and looks nice but isn't really that high-end bike that demands the very best components and certainly doesn't draw oohs and aahs from the bike snobs. Enjoy the ride with smooth, nice functioning components.
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Size: 68 x 123 Verified Purchase
In my old age, I have lost patience with loose ball bottom brackets and if they give me any grief at all, I yank 'em out and put in cartridge BB's like this one.

I use the ordinary Shimano ones like this and have never had a problem with any of 'em in the fifteen years I've been doing this on my own and others' bikes.

You do have to make sure you get the correct threading, shell width, and axle length, of course.This size, 68 x 123 mm, fits a lot of low end and mid-grade mountain and hybrid bikes but you need to measure to be sure.
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Size: 68 x 123 Verified Purchase
Bottom brackets shouldn't just break. Mine did.
According to the instructions on my bike, the bottom bracket was a Shimano. But when I pulled it, it was a different brand. Maybe that's why it broke?

The Shimano BB-UN26 is a pretty common cartridge on bikes. This one has a hard plastic locking ring/sleeve, which is my only complaint. Having said that, the plastic might allow for easier replacement on threads that are rusted or damaged. Just pay close attention to the instructions, because you do not want to add a petroleum product onto a plastic locking ring.
Pay attention to the direction of the threads!

If you have a torque wrench, use it. This is the 3rd time I've been able to use mine, and it felt good to know that I was torquing the bracket to the correct tightness.
Best of luck.
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Verified Purchase
Very easy to install; runs very smooth. I'd deduct a star for the plastic washer except that it doesn't seem to degrade the performance and at this price it seems like a worth trade-off. If you are concerned about the plastic piece, the next model up is all metal.
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Size: 68X122.5
this BB is fine for onroad and light off road but it may be worth the extra 8 bucks for the UN54 which runs much smoother and is by far stonger.
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Size: 68 x 123 Verified Purchase
I bought this bottom bracket as a replacement for original equipment on a Diamondback mountain bike. I noticed that despite my effort to match the dimensions, the bottom bracket wouldn't thread fully into the bike but I don't fault the product for that and in any case functionally it works just fine.

The action of the bottom bracket is very smooth. The plastic cup included with the product got a bit beat up as I tried to install it, so I ended up keeping the original metal cup from the original equipment bottom bracket. I would have preferred a metal cup.

Overall, based on the Shimano brand and reasonable price, I would purchase the item again and so far it is performing well.
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Size: 68x110-mm Verified Purchase
Ordered this to convert a triple crankset to a double crankset.

Other than the weight, which is to be expected at this price point, this is a solid bottom bracket that will work for years without any maintenance.

Source: I am a professional bicycle technician with over 15 years of experience.
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Size: 68x122.5-mm Verified Purchase
Cheaper alternative to the UNBB55, but works the same.

Only complaint is the plastic non-drive ring; may be easily damaged during tightening. Just be careful when you're threading it in.

I replaced an old cartridge bearing BB with this one. The cartridge bearings, spindle, and cups were damaged beyond repair.

Much better than the old cartridge. It's sealed and it spins with less friction.

Grease the threads with a non-petroleum product as it may damage plastic cup. Alternatively, you may use a medium strength Loc Tite.

Great price, great seller (resides in my state, fast shipping). Good quality and looks to last for years.
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