I have external HT2 BBs on 2 mtbs, ancient square taper on another, older Dura Ace octalink on my road bikes and Campag square taper on my fixed gear commuter.

I can’t feel any difference between them when riding.

Sadly, the commuter is the bike ridden most often (especially through the winter) but is looked after and cleaned the least. It gets hammered along canal towpath and potholed roads in all weathers then dumped in the garage upon arrival home, with the occasional oily rag wipe and squirt of lube.

Its had loads of different cranks and BBs in its time – I’ve wrecked some through overtightening in the past. At the moment it has a Campag Veloce BB with Centaur cranks, which have been fine for ages… until this week when I noticed some play in the drive side arm. I’ve been careful with these ones, checking the bolts pretty regularly and making sure I hadn’t overtightened. Weird that it appears to be the drive side that’s developed a problem.

Made me think though – does popular opinion still reckon that square taper is the most resilient interface? TBH I’ve always liked Octalink the best, but I don’t know if it would hold up as well on a fixed gear with a 48:16 ratio. I like to stamp my way up hills!

Getting fed up having to pay attention to it – I just want something I can fit and forget!

you don’t seem to know the meaning of “robust” but yeah, a good ol shimano sealed Square taper BB will probably outlast most other BB types in terms of bearing wear/play

My 1993 UN91 square taper BB is still buttery smooth 😯

I run two UN72 square taper BB’s on two other bikes and TBH I have never killed one 😕

I have just got a KCNC external BB which I do wonder how long it will last 😈

Square taper = fit and forget.

Simples

Most will say square taper are strongest and isis are made of cheese because of the weeny little bearings. Ive had an isis on my ss bike for over three years and it hasnt made a peep, Ive been through three or four the hollowtech types on the other , less used geared bikes in the same period.

When I was speccing the bike I was wondering about whether to go square taper as generally the BBs themselves last for ages or go for isis as its reckoned to be a stronger interface system, I decided against square taper as too many user reviews said cranks rounding off made them a pain in the arse especially on ss, all that stomping up hill I guess, so I went isis and its been spot on.

There will of course be lots of people with exactly the opposite view and experience. I read loads of posts from people who go through isis BBs in a month or two.

Chris hoy uses square taper 😀

catfood – Member
Most will say square taper are strongest and isis are made of cheese because of the weeny little bearings. Ive had an isis on my ss bike for over three years and it hasnt made a peep.

is anyone on here really naive enough to think that square taper BBs are strongest system? and until I used the superstar IRB ISIS BB no ISIS BB ever lasted me more than a couple of DH runs without developing slight play (which increased over time until it was unbearable but never actually failed/seized)

is anyone on here really naive enough to think that square taper BBs are strongest system?

There seem to be a small but vocal group who swear by them. I should have said that some think square taper are strongest (most durable) not most think it.

Square taper BOTTOM BRACKET BEARINGS last a long time. The cranks, however, are easier to wreck, and the axles bend too easily for my liking….
I wouldn’t put SQ taper on an MTB any more. Commuter, yes no problem.

is anyone on here really naive enough to think that square taper BBs are strongest system

Uhhhm, yeah right we are all naive 🙄

I suspect most long term cyclists will agree that the Shimano square tapers (the better ones anyway) pretty much last forever. Whereas the external type seem lucky to last a winter.

Now this is longevity and robustness we’re talking about not overall strength – as the external type will be stronger as they have wider spaced, larger bearings. BUT they don’t last as long due to sealing and other issues.

If you want to talk strongest and most robust then the Truvativ Howitzer BBs take some beating – the bearing size advantages of the external type and the sealed cartridge advantages of the square taper type. Had a set on my winter SS for 2 years now with not a peep out of them.

“strongest” and “most durable” are two very different things.

“strongest” and “most durable” are two very different things.

Not in BBs it’s not! 🙂
For instance: If the bearings are durable, but the axle is not strong, then it won’t last very long, will it?

Have you ever snapped or bent a BB axle PP?

Not to say that they are necessarily stronger but ….. In 20 years of cycling I have never bent, damaged or totaled a square taper BB.

I have one in my Soul at the moment.

I understand that only time will tell but from previous experience I am expecting no problems 🙂

6 year old UN52 in my klein sits in the same damp garage as my 3 sets of external BBs and rides in the same wet weather, gets washed with the same hose.

Some of the external bearing last no more than a month.

Whilst i accept that external is a stronger, stiffer and more durable CRANK system, as far as bearing durability goes square taper is by a long LONG way the best

I have GW, I snapped a square taper axle years ago. Now I use external bbs, and I’ve never snapped one of those axles.

Have you ever snapped or bent a BB axle PP?

Yep. And had damaged tapers on a crank. I never had much luck with SQ taper, I was sooooooo glad when there was an alternative, and HT2 seems unbreakable to me. I get a good year+ out of a HT2 BB, which is more than I ever had out of Sq taper, it’s a lot easier to change it when the time comes, and there’s not umpteen different sizes, making switching cranks over a doddle

Here here Mr MW. My SS runs square taper and middleburns because they last ages and that bike takes most wet and muddy conditions abuse. Get through many more bearing sets in the nice light and stiff HT2 setups with less abusive riding conditions.

Octalink are the best compromise between the two in my experience.

For the crank breakers out there – eat less pies or learn to ride with more finesse 😉

About 4yrs ago I bought a s/h campag record square taper b/b of here. 20,000+ road miles ( for me ) and its still going strong. The only prob you can get with sq/taper btm brackets is rounding out your cranks, if they get a tiny bit loose and you like drops, jumps etc.

For the crank breakers out there – eat less pies or learn to ride with more finesse

I’ve never broken a crank, but you tell me how to land without stressing the tapers on a Sq taper BB with my feet still on the pedals, and I will do….

One crank is trying to turn the axle one way, the other is trying to turn it the other way….. Something’s gotta give!

You’ve got 3 pieces, not 2, and the joints have 4 small flats each, not a big splined axle. It’s plainly obvious which is going to last longer. 🙂

I’ve had 4 years out of my XTR HT2 crankset, running through 2 Shimano BB’s quickly and now Hope ceramic for over 2 years – no problems at all.

My kids though have managed to wreak getting on for a dozen ISIS/square taper BB’s and cranksets in the same time… and probably a tenth of the miles/usage.

I’ve never broken a crank, but you tell me how to land without stressing the tapers on a Sq taper BB with my feet still on the pedals, and I will do….

You could always try absorbing the impact with your body. 😛
I’ve bent/snapped/twisted plenty cranks/axles in my time and square taper never lasted too long for me either for exactly the reason you state but if you’re light on cranks a decent sq taper BB will probably outlasting a HTII spin freely one by quite a way. There’s nothing wrong with 3 piece cranks if done well tho (ie. splined cromo)
FWIW Cheapy Deore HTII BBs last me a good 2 years+ with my saints before they develop play. but my old square taper ultegra road BB is still original (from 1999).
<EDIT> sorry, my point was, if you aren’t harsh on cranks or tapers, know how tight a SQ taper axle bolt should be and use decent quality cranks in the first place SQ taper will be more durable for you (it’ll never be the strongest, hence my distinction between strength and durability) not everyone needs strong!

Oh dear PP, I seem to have touched a nerve and I have no idea how many pies you eat 🙂

You may not have snapped a crank or BB but you have broken them if the tapers are giving up.

I’d take issue with HT2 being 2 pieces – slightly simplistic as they aren’t but you can only easilly dismantle into 2 parts. I guess that’s one less side to get wrong though if mechanically inept. Not that you could suggest anyone here is of course.

I love the longevity and fit and forget nature of square taper, the octalink stiffness and good bearing life at low cost, the very light and stiff feel you get from HT2 and equivalents – though it is just as well they come apart easily to replace bearings.

The other HT2 benefit is they are soooo much less likely to get the chain jammed when experiencing chain drop/suck.

Nothings perfect though eh?

You could always try absorbing the impact with your body.

It’s gotta transfer through to the floor somehow! Simple laws of physics! 🙂 I’m generally pretty smooth though, but I’m not afraid of a few small drops….

but if you’re light on cranks a decent sq taper BB will probably outlasting a HTII spin freely one by quite a way

I’m light on the cranks on the road, and that’s the last place I used a SQ taper BB, and yes it was fine for 1500 miles before I sold the bike. I’ve not used one offroad since my first Octalink in 2004 (I didn’t ride for about 6 years before that) and I wouldn’t again for the reasons already stated.
Sq taper lasts brilliantly until I give it some stick, then it packs up on me, so I don’t use it any more for that. Simples. 🙂

the longevity and fit and forget nature of square taper,

For me it’s not like that, sorry. They creak, come loose and bend. I never had one last more than a year of MTB, and I ride more now than I ever did on SQT. Octalink are meant to be good too, but I only ever had 2 of those and both wore out in under 800 miles (Not broken, just worn out)
I don’t get a massive amount more from HT2, as I said, but I don’t wreck the tapers, they never, ever need checking* and it’s a LOT easier to replace the BB or switch it between frames (You can’t argue that switching SQT between frames often needs a new BB!) 🙂

* I did have an FSA one that wouldn’t stay tight on the axle. CRC replaced it for me, the replacement was the same, so I asked for an XT which was fine, and I still have it. Dunno what was up with the FSA….

EDIT
I’ve tried a few systems and makes over the years, and a process of elimination has lead me to sticking with Shimano and HT2. It’s not like I haven’t “sucked it to see”!

EDIT 2
I don’t bother with the flash stuff. My 2 main bikes both have Deore cranks, my SS has some 5 year old LX and the XTs mentioned above are on my commuter.

It’s gotta transfer through to the floor somehow! Simple laws of physics!

that doesn’t even make sense! 😕

I’m generally pretty smooth though, but I’m not afraid of a few small drops

is this on the beefed up pitch you’re always posting pics of?