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Shimano UN-73 Bottom Bracket
Item #: BB708A01
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USD$12.99 48% off USD$24.99 msrp
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Customers Also Bought
A solid, reliable square taper bottom bracket, the UN-73 Still one of the best overall square taper style bottom brackets available, an oldie but goodie.
- English Threaded
- Hollow chromoly JIS spindle
- Fits square taper style cranks
- Weight: 242 g
REVIEW SNAPSHOT®
by PowerReviewsShimano UN-73 Bottom Bracket
(based on 18 reviews)
Ratings Distribution
93%
of respondents would recommend this to a friend.
Pros
- Price (3)
Cons
Best Uses
Most Liked Positive Review
Awesome especially for the price
I've built and ridden a couple dozen bikes using this BB or one below (like the UN-54 and such) over the years, and i personally can't tell the difference between a really high...Read complete review
I've built and ridden a couple dozen bikes using this BB or one below (like the UN-54 and such) over the years, and i personally can't tell the difference between a really high end vs. a low end square taper BB other than the weight. So many of the external/integrated BB types really blow the square taper + ST crankset combos out of the water when it comes to weight and stiffness... so when you go square taper i figure you're on a tighter budget or riding a somewhat unique BB shell or crankset. And in either case, these BB's are great. I haven't done too many thousands of miles on any single UN-73 or the like... but i've done many hundreds on most, and i don't think general users buying these Shimano BB's either reach those kinds of miles, or alternatively don't mind replacing their BB's every 3 to 5 years of real use.
Them's my two bits.
VS
Most Liked Negative Review
Cheap part replacement
Cheap replacement part. The plastic parts make me a little worried about how well it will stand up to abuse. We shall see.
Cheap replacement part. The plastic parts make me a little worried about how well it will stand up to abuse. We shall see.
Reviewed by 18 customers
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Displaying reviews 1-10
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Pros
- durability
- Performance
- price
Cons
Best Uses
- Commuting
- Fixed gear
- Road
Comments about Shimano UN-73 Bottom Bracket:
I threw one of these in a fixed gear commuter that I built up a couple years ago. It has worked well through all the abuse I put it through, and still spins perfectly today. No complaints at all--a great component for not much money.
Pros
- Durable
- Inexpensive
- Smooth
Cons
- Heavy
Best Uses
Comments about Shimano UN-73 Bottom Bracket:
This bottom bracket has been powering my commuter for five years. It's a simple, tested design that seems all but impervious to the grit and dirt encountered on a daily commute.
Some reviewers have hesitated about the plastic non-driveside cup. This poses no problem if properly installed. It's not designed to be torqued like the driveside -- just enough so the bottom bracket is secure. Over torquing plastic will cause it to crack.
When installed correctly, this bottom bracket will last for years.
A bit heavy, but for under $20 what do you expect?
Comments about Shimano UN-73 Bottom Bracket:
Replaced the one in my Fisher Big Sur that is 14 years old. Got rid of some creaking and spins nice and smooth.
Comments about Shimano UN-73 Bottom Bracket:
These 7x series BBs are nice, I believe they are still made in Japan. I'd rather use these than one of the 2x or 3x series. I think the 5x are fine -- the only difference is they don't have the hollow spindle (a few grams). But at the price Jenson has them, this is the one to get. Thanks.
Comments about Shimano UN-73 Bottom Bracket:
Perfect square taper bottom bracket. Very smooth and light for this old style.
Comments about Shimano UN-73 Bottom Bracket:
It works as it is intended, smooth
Comments about Shimano UN-73 Bottom Bracket:
This is Shimano's top level square taper bottom bracket and it shows. Metal cups, super smooth action, works great with the corresponding crankset.
Pros
- Compatibility
- Easy To Install
- price
- Quality
Cons
Best Uses
Comments about Shimano UN-73 Bottom Bracket:
Great bottom bracket for the price. I was able to keep an older mountain bike that I converted to a cross bike on the road for a few more years.
Pros
- cheap
- Lightweight
Cons
- none
Best Uses
Comments about Shimano UN-73 Bottom Bracket:
I used this to replay the old BB on my son's bike. It was relatively lightweight (264g) for such a cheap BB, has smooth bearings and is one of the better Shimano BBs of the old square taper variety.
Pros
- Great Value
- Well Made
Cons
Best Uses
- You know what to do
Comments about Shimano UN-73 Bottom Bracket:
[$] is cheap but great quality = great value.Comes in a good selection of lengths, bought the 122.5mm version to get the right chainline for my crankset.Plastic cup is fine, have used shimano BBs with plastic cups on a number of bikes to fit older cranksets and had no issues.
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
