In this article I’m going to cover the top 6 best square taper bottom brackets.
My 1994 Cannondale Super V keeps having issues, which is somewhere located in a rotating part of the drivetrain. Since I’ve changed the cassette, chain and even both front chainrings, there’s only one thing left aside from the rear suspension. And that’s the bottom bracket.
It’s a Shimano BB-UN52 for a bottom bracket shell of 68mm. with a spindle length of 110mm. which was very standard MTB stuff for the time.
I bought it second hand with the Cannondale Tarantula crankset in a bulkdeal, because it’s the one that came with the bike. It also meant it was already over 2 decades old. And now I know that probably one of the cartridge bearings is broken.
Since I’ve been upgrading the entire bike, the necessity of buying a new part means I can yet splurge on something else. But only after I’ve done some proper research into what makes a good bottom bracket, and what are some alternatives to the tried-and-true Shimano ones.
I’ve also written an article about the overall quality of square taper bottom brackets when compared to Hollowtech II bottom brackets..
So here’s my list of the best square taper bottom brackets. It covers the JIS square taper versions (no campy stuff) with English threading.
What to look out for in a high-quality square taper bottom bracket
The best square taper bottom brackets are different in certain departments. Here’s what to look out for.
- Spindle: Your standard spindle will be made from chromoly steel. Some spindles are hollow to reduce the weight. And you can find titanium spindles as well (Phil Woods & Token), which is a very expensive way of reducing weight as well.
- Shell: Where aluminium is your basic lightweight option, you can find both stainless steel (SKF) and carbon (Token) on more expensive models.
- Cups: Don’t shoo away nylon cups, since they’re a valid option to put in steel frames, so you’re certain they’ll never seize. That being said, almost all expensive models come with aluminium versions and even stainless steel.
- Bearings: Bearings are of course a key component of any bottom bracket. And bearing size matters when looking for longevity. Bigger bearings (SKF) mean longer lasting (in general) and premium bottom brackets run oversized cartridge bearings. Another way of thinking about bearings is how smooth they run. And opting for ceramic bearings (Token) is one way to keep having that smooth run.
- Bearing Seals: The key to have a long-lasting square taper bottom bracket is keeping contaminants out of the bearings. You achieve that with above-average bearing seals (SKF).
Shimano BB-UN300 square taper bottom bracket
If you want a replacement for any older style Shimano square taper bottom bracket, like my BB-UN52, the current offering is the Shimano BB-UN300. It’s the only bottom bracket by Shimano specifically meant to replace your worn bottom bracket. And the only bottom bracket available in different spindle lengths.
The BB-UN300 is by far the cheapest one on this list of best square taper bottom brackets. That doesn’t meant it isn’t a viable option. Shimano is a huge company, which enables it to do things at scale to keep costs low.
Their value-for-money products have been putting other component manufacturers out of business since the 80s, so if you don’t want to spend more than €12.99 for a solid quality bottom bracket, the BB-UN300 is your weapon of choice.
Shimano BB-UN300 Specifications
|Length||Shell width||Buy at Amazon||Buy at Ebay|
Shimano BB-UN55 square taper bottom bracket
The predecessor of the BB-UN300 and follow-up for the BB-UN52, you can no longer get the BB-UN55 but it’s still readily available on Ebay.
You definitely won’t get a better price on a BB-UN55. In general NOS parts on Ebay are pretty expensive.
There seems to be a lot of discussion about the BB-UN55 vs. the BB-UN300. After decades of use the square taper bottom bracket is definitely going out of style, and with it the demand for high-quality ones.
The BB-UN55 seems to be the last of the Mohicans in the high-quality bottom bracket department from Shimano. With the difference located in above-average bearings and bearing races.
This bottom bracket has been a staple in thousands of bicycles being ridden for multiples of that in miles. So I have no reason to doubt its longevity in any way.
Shimano BB-UN55 Specifications
Miche Primato square taper bottom bracket
If you like made in anywhere else but China you might like the Miche Primato square taper bottom bracket. Made in Italy it comes in two lengths of 107 and 110mm for a 68mm. shell.
2 7075-T6 grade aluminium (very tough) cups keep everything in place. Weighing in at 210 grams, this bottom bracket is pretty light on its feet.
Miche Primato Specifications
Phil Wood square taper bottom bracket
What do you get when are willing to pay more than €100 (starting price $158) for a square taper bottom bracket. Well, you get a very expensive piece of kit that’s fully serviceable, offers a (optional) titanium spindle for the Pro model, and (optional) carbonyte bearings.
They don’t give the bottom bracket a name other than calling it a square taper bottom bracket.
And you get them without cups, which are available for an added $46.30. That means you can choose the cups you want other than the standard 68mm. English threaded versions.
I won’t offer a table here because of all the permutations, but safe to say Phil Wood has got you covered in the bottom bracket department if you’re willing to pay the money.
I’ve never considered a square taper bottom bracket to be a piece of bling on your bike. Basically because you don’t see it, so there isn’t much to bling in the first place. And I’ve never used a Phil Wood bottom bracket so can’t say anything about the quality, but for this type of money I bet it deserves its place on this list.
Is it worth spending that much money on a single part? Sure it is, if you plan on enjoying it for many miles and years to come. If you have a certain budget in mind, and a Phil Wood bottom bracket will push you over its limits, I believe you can just as well go for the Shimano BB-UN55 and get the same type of ride out of it.
Token square taper bottom bracket
You want a lightweight bottom bracket, optional titanium axle and ceramic bearings, so you can save that weight and have a 155 grams square taper bottom bracket compatible with old-skool dual and triple cranksets? You want the Token square taper bottom bracket.
They achieve this light weight with a body made of carbon fibre, and of course it comes with alloy cups and a set of bolts.
For the “standard” bottom bracket you pay around €40. If you go premium with the titanium axle and ceramic bearings, expect to pay north of €100.
|Length||Shell width||Crank type|
SKF BAS-600 square taper bottom bracket
Known for their expertise in bearings, German manufacturer SKF also offers square taper bottom brackets.
Special multi-seals keep contaminants away from the bearings while keeping the grease inside.
The bottom bracket comes with a 10-year warranty which says a lot about their confidence in the product.
Anyway who’s ever tried to remove a rusted bottom bracket understands the value of stainless steel. The BAS-600 is made from stainless steel so don’t expect it seizing into your frame.
Using stainless steel instead of a chromoly spindle does make the it somewhat less strong.
The one downside I can think of, besides the price of around €150 and the difficulty in obtaining one, is the fact you’ll need a Park Tool BBT-4 6-notch bottom bracket removal tool.
SKF BAS-600 Specifications
That wraps up my top 6 best square taper bottom brackets.