Square Taper BBs that lasts more than 5s

Running a UN300 on my commuter for the last 12 months. No issues at all. Not as well made as the UN54, but so far so good

The OEM in my charge Fixie is an FSA IIRC, still going strong after thousands of cruddy miles in my ownership, and the bike was battered long before I got it and stripped it down primarily for the frame

There's a lot at 107mm in SJS Cycles, but not the UN55 unfortunately.  I am surprised the un300 didn't last. I have had good life out of cheap shimano ones before.

Middleburn are the highest quality I have come across and used successfully for years. Now available through BETD after acquisition.

I spent hours trying to find a creak that couldn't possibly be the BB as it was less than a year old.
It was the un 300 piece of rubbish.

Yeah they are crap. This one is behaving like it has been jet washed then left in a river for a month. Sadly had to put another one in as need the bike working asap but don't want to leave it in long term.

BETD/Middleburn don't seem to do a sq taper any more.

I'd seen the SJS options but was hoping some of those would come up as recommendations.

I have a un72* in the spares box but unsure of size.  I don't have any ST cranks so can't see this ever being used again be me.

*It might not be a UN72 but can check although probably not 107mm

Funny innit, cos the old XTs lasted forever. I had some (prior to my recent garage clear out) that were from the 90s and still the bearings were smooth running.

^UN72s, that was them. Lovely.

The issue with the UN300 is the non-drive side bearing sits outside the shell, and held in place by the locking cup. Whilst it can be regreased, and has an extra seal, this must be a weak point.

Spa Cycles. I think I have the DX30 on my 1995 steel winter hack. Seems to be lasting well.

https://spacycles.co.uk/m16b0s110p0/Bottom-Brackets-%7C-Headsets-%7C-Bearings/Bottom-Brackets

Tange LN7922 is my go to square taper although I’ve just fitted a UN300 into my singlespeed out of curiosity.

The one on my commuter is a 2nd hand Un55/57 off eBay.  Was lightly used when I bought it and 2 years of fair weather commuting later, it's still fine.

Yeah, been through two UN300s in 12 months. They're crap compared to the old UN52/UN72.

<p style="text-align: left;">Phil Wood - expensive, but will probably outlast the frame.</p>

Look to get a 2nd hand one off ebay.

I can't find the order history, but I THINK this is the one I bought recently from Spa cycles.

https://spacycles.co.uk/m16b0s110p3233/FIRST-COMPONENTS-DX-30-Bottom-Bracket

It has an additional seal in the cup that runs on the axle, so an extra line of defence before the bearing shields themselves. Not expensive and available in the 107 you're after, (plus an unusual 120mm that I needed, why I think this is the one I purchased). Only been installed a couple of months so I can't comment on longevity.

Phil Wood – expensive, but will probably outlast the frame.

if it were my bike perhaps but not for this one.

Will give either the DX30 or Tange ones a go I think as both seem widely available.

Good shout on Tange. Their FL270C headset is a fabulous bit of kit. I used them on my 90s Konas and commuted in all weathers. Cartridge bearings, good seals, low stack height, great look and finish, and £25!

You're probably aware already being a square taper aficionado, but watch out for JIS/ISO taper mismatches.

Square taper hater but needs must for short kids cranks. Cranks are JIS so all good.

Running a UN71 and a UN91 on my road bikes. Must be 30 years old now.

@nixie

Link shows that Middleburn/BETD are still doing a number of square taper. You'll have to go through and see if they meet your requirements.

Middleburn square taper

@lotto, thanks but those are cranks not BBs.

@nixie

Total brain fart there. I don't know what I was thinking.

What about Royce? I believe these are considered the Rolls Royce of BB's.

stronglight  jp400 aluminium

mine has done a few 1000 miles and still ok.  from Spa.

https://spacycles.co.uk/m16b0s110p140/STRONGLIGHT-Bottom-Bracket-JP400-Aluminium

TA Axix. Very pricy, but it has replaceable bearings, just takes “standard” cartridge bearings, or, at least, my old one does.

I’ve had one on my fixie for 16 years with about 3 bearing changes.

Are Royce still making bottom brackets?

IRD Quad QB55 from SJS, available in 107 (and not much else at the mo!)

Good quality at reasonable price; I've only put a few thousand miles on mine and a lot of those on Zwift, but the fit and feel of it gave me good tingles for longevity

ton
Full Member
stronglight jp400 aluminium

Not sure what models ours are, but deffo Stronglight from Spa.

Have them on three bikes and they've been soaked in sea water a few times on the way over to Lindesfarne and after a bit of a clean up are still running fine.

As are the Stronglight cranks, Deore hubs and Exal rims they recommended.

Note on the IRD : they’re tange ln7922 but with sexy packaging. I fitted one of the QB95 defiant to a build and was nonplussed to note the similarities with the tange ln. Of course the giveaway on the IRD box was; made by Tange.

I have an old Real BB from early 90s on one of the single speeds. Relaceable bearings and actually decent seals (also an off the shelf part if i remember correctly) - might be worth trawling the retro parts spots to see if a second had one turns up. And due to impending employment difficulties, mine will be making it's way onto flea bay soon....

I'm guessing regular local bike shops must have a few immortal UN7* knocking around? They were ubiquitous for decades I think...