I’m looking for some feedback on the square taper BB. I currently have two bikes using them (Sugino SS cranks/ matching bb) and for the most part like them. I going to build up a SS cyclocross bike and just wanted to reaffirm by preferences. My other option would be the Sram GXP bb.
Dave in VA
Other than they are slowly becoming obsolete, the only real con is that the tapers can be worn out on the crank with repeated removals. Also too heavy a hand putting them on can damage a crank, but both situations are relatively avoidable. The newer systems, while nice in some ways don’t really improve on square taper in any substantial way.
Styrrell
Pros
Bottom Brackets seem to last forever.
Cranks are cheap
Easy to take on take off
Cons
Bottom brackets are getting harder to find
Not as stiff as outboard bearing cranks
Interface to bottom brackets can get loose over time
Sometimes crank bolts start to get loose despite having loctite
If you are on a super tight budget might not be a bad idea, but I would get some of the newer cranks if possible.
If you’re having to put loctite on crank arm bolts, it’s too late they’re already ruined. The hole in the crank is either rounded out from being too loose or split from being too tight.
Square tapers should be torqued to the correct spec after being completely remove and then left alone. The bolt preload will cause the arm to move inward and the force will equalize. Continuing to tighten the bolt after that will the force the crank farther onto the spindle until the arm splits.
The unfortunate thing was that square tapers were predominant when most bike shops didn’t even know what a torque wrench was, so they we installed by feel and a lot of them ended up too tight or too loose.
Square taper BB has stood the test of time. It will never go obsolete. The so-called advantages of the newer designs are tiny, if they exist at all. If you are happy with what you have, why change?
Frank
I don’t really think you’re going to have any trouble finding BB’s for the next few decades. There are a lot of square taper bikes out there, including the majority of bicycles produced today (yes, they actually make bikes that cost less the $500.00…).
There’s one primary advantage to external BB cranks: removing them frequently doesn’t wear the crank. For a cross bike, I could see that being a consideration–makes it easier to clean the crank when it’s off the bike.
Disadvantages, as others have mentioned-the BB’s don’t wear nearly as well.
My belief is that the function problems with square tapers, listed above, are very rare. Availability is a little bigger issue, but I’m guessing that NOS will be out there on EBAY for a long time. A few years ago I picked up a suntour superbee pro bb that was NOS from 15 years prior. Personally, I’m betting st bb’s will be readily available for some time. Your bike store might not stock, but Ebay will have them.
Square crank tapers and round tubing frames have been winning races for over 100 years. And we are "improving this why? I have a Phil Wood BB and Campy crank that is going on 37 years without any maintenance, explain why this is a bad thing please? I have 3 NOS Record cranks in stock for future projects ( they all came off the Ebay for around $100-120), and as long as Phil Wood is in business I am set. I do have a couple outboard cranks on bikes and really don’t see any advantage to maintenance or ease of installation at all. If you have the right tools BB s aren’t that tough of a change out. Between the Phil BB and Chris King HS, I won’t be replacing those parts very often.
I agree with you and Frank…why the hell did they have to muck with a perfectly good bomb proof part. I have a mountain bike with which I bike commuted through 8 Canadian Salt laden winters. That bike is now 18 years old and I still use it and have never touched the BB once!
My powercrank bike (a 1999 Kestrel 200SC) has taper square (so it is going on 10 years), and I have not touched it once for maintenance either even though I have swapped out regular cranks and the powercranks numerous times on and off the bike.
Taper Square is bomb proof and everything else are creaking noisy gimmicks designed to make us part with our $$$$$ for what amounts to marginal incremental utility (kind of like the diff between windows upgrades…performance just gets worse and worse…the software guys at Microsoft suck compared to their marketing guys who must be genius’ making us use their crap).
Dev
I don’t really think you’re going to have any trouble finding BB’s for the next few decades. There are a lot of square taper bikes out there
OTOH, the Shimano Octalink b.b. seems to going the way of the do-do bird, at least if you’re looking for something with sealed bearings and a spindle that won’t rust. 
(Yes, Al, I know that it is possible to replace the bearings of a BB-6500…just haven’t worked up the energy yet.)
I agree, my $300 bike with square taper crankset, it was made fun of by the local bike shop
but it is still going
the one that came on my cervelo, died within a couple hundred miles
someone put some sweet carbon crank arm square taper stuff on the market =)
.
My tri bike is a 1989 Klein Quantum on which I recently replaced the crankset with a new tapered Chorus 53/39 and replaced the bearings. These were the original bearings and had never been removed (they are pressed in). I fully expect this crankset and bottom bracket to outlast me.
There is no issue with availability - the track set almost always run them, and lower end bikes are often spec’d with them. Big simple bearings, simple design, they will not go out of style.
A Miche Primato BB doesn’t cost more than $40 CAD and every time a cyclocross bike comes in with a bottom of the barrel BB the customer is always happy to have it changed. Heck, you can even spend a couple of bucks and get something from White Industries.
The only time I have had issues in the shop with a square taper was on someone’s beater from 30 years ago that has never been serviced or if the owner has been doing some “home servicing” without the right tools.
p.
… Taper Square is bomb proof and everything else are creaking noisy gimmicks designed to make us part with our $$$$$ for what amounts to marginal incremental utility (kind of like the diff between windows upgrades…performance just gets worse and worse…the software guys at Microsoft suck compared to their marketing guys who must be genius’ making us use their crap).
Dev
I shit you not… just as I was reading the above --didn’t even click anything – IE spontaneously crashed on me. Had to re-launch just to chime in agreement.
Still running square tapers on 7 of my 9 bikes (+ one octalink and one current external-type). If it ain’t broke, don’t fix it. And if you swap stuff around a lot like I do, it generally gives you more flexibility between different brands/styles of cranks.
I have been using square taper BBs for years and have had no issues. If you are referring to the Sugino RD cranks, they are very nice! I used them on my fixed gear for quite some time and had no problems with them.