Who designs this stuff?
#1
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Who designs this stuff?
Well, a 7 year old crankset now has the value of a case of crushed PBR cans. The press fit steel spindle and aluminum spider interface started giving way, and now I can't trust it anymore for fear of total failure on the road. I'm peeved, since compared to all other cranks and bottom brackets I have (all square taper), none have ever let me down, and are still going strong. Who came up with this design "improvement"? Sure the BB can be installed quicker by some machine or unskilled person, but aside from that, where's any advantage?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
Last edited by Point; 07-22-13 at 08:26 PM.
#2
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Joined: Jul 2011
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From: Ogden, Utah
Bikes: CAAD 10, Cervelo P2 SL, Focus RG-700, Quintana Roo #101
Well, a 7 year old crankset now has the value of a case of crushed PBR cans. The press fit steel spindle and aluminum spider interface started giving way, and now I can't trust it anymore for fear of total failure on the road. I'm peeved, since compared to all other cranks and bottom brackets I have (all square taper), none have ever let me down, and are still going strong. Who came up with this design "improvement"? Sure the BB can be installed quicker by some machine or unskilled person, but aside from that, where's any advantage?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
#3
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From: Merry Land
Bikes: Guru Evolo R, Colnago Pista, Look AL 464P SS, various frankenbikes
When well designed and manufactured, it's both lighter and stiffer, the elusive formula all cycling component developers seek. Some are certainly built better than others though.
#4
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Quick installation means cheaper build cost, means cheaper price, means more sales. The manufacturers don't necessarily share your passion for long lived equipment. Turnover means profit.
---
Re road triple or compact, there is a cheaper way. I do this because I go on one or two euro-mountain-pass cycling weekends per year - but spend most of the time in flatter regions near home.
Get a mountain bike cassette (I use a 32t lower), a longer chain to go with it and long cage derailleur. I keep the 3 of them together - switching the set over for climbing holidays. It's not as low geared perhaps but it sees me up big hills often with a gear or two to spare.
---
Re road triple or compact, there is a cheaper way. I do this because I go on one or two euro-mountain-pass cycling weekends per year - but spend most of the time in flatter regions near home.
Get a mountain bike cassette (I use a 32t lower), a longer chain to go with it and long cage derailleur. I keep the 3 of them together - switching the set over for climbing holidays. It's not as low geared perhaps but it sees me up big hills often with a gear or two to spare.
#5
The opposite of your BB is my 20 year old sealed bearing Campy BB that came with my Merckx. Many thousands of miles and it has been flawless. I talk to friends about newer ceramic Campy BB's that cannot tolerate dirt?! Utter failure of utility. All of my '92 Chorus parts have been worthy heirs to the Nuovo Record groups I rode before. Makes me afraid to buy newer stuff.
#6
pan y agua

Joined: Aug 2005
Posts: 31,812
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From: Jacksonville
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Well, a 7 year old crankset now has the value of a case of crushed PBR cans. The press fit steel spindle and aluminum spider interface started giving way, and now I can't trust it anymore for fear of total failure on the road. I'm peeved, since compared to all other cranks and bottom brackets I have (all square taper), none have ever let me down, and are still going strong. Who came up with this design "improvement"? Sure the BB can be installed quicker by some machine or unskilled person, but aside from that, where's any advantage?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
So much for complaining - any opinions on keeping the triple or going compact double for the replacement?
Like there were never any problems with Square taper cranks. Aluminum crank arms will fail over time where the arm attaches to the steel spindle, with the hole in the crank arm enlarging, particularly if the crank is ridden with the fixing bolt just a bit loose.
Old square taper internal BB's had an advantage with friction, over modern external sealed bearing bb's, but I don't think many people would maintain that square taper is a superior interface for attaching a crank arm to a bb spindle.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
#7
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The opposite of your BB is my 20 year old sealed bearing Campy BB that came with my Merckx. Many thousands of miles and it has been flawless. I talk to friends about newer ceramic Campy BB's that cannot tolerate dirt?! Utter failure of utility. All of my '92 Chorus parts have been worthy heirs to the Nuovo Record groups I rode before. Makes me afraid to buy newer stuff.
#8
Old fart



Joined: Nov 2004
Posts: 26,411
Likes: 5,350
From: Appleton WI
Bikes: Several, mostly not name brands.
(still using my 30+ year old equipment here)
#9
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Lighter? A Shimano 600 crank from 20 years ago weighs about 600 grams - add in 300 grams for a square taper BB and the weight isn't that far off a modern crank - a new Ultegra double and BB combo weighs 960 grams. As for stiffer, the small amount of torsional bending in the spindle isn't worth mentioning, and the external cups don't do a thing for lateral deflection anyway.
#10
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Like there were never any problems with Square taper cranks. Aluminum crank arms will fail over time where the arm attaches to the steel spindle, with the hole in the crank arm enlarging, particularly if the crank is ridden with the fixing bolt just a bit loose.
Old square taper internal BB's had an advantage with friction, over modern external sealed bearing bb's, but I don't think many people would maintain that square taper is a superior interface for attaching a crank arm to a bb spindle.
Old square taper internal BB's had an advantage with friction, over modern external sealed bearing bb's, but I don't think many people would maintain that square taper is a superior interface for attaching a crank arm to a bb spindle.
#11
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Joined: Dec 2009
Posts: 28,682
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From: Houston, TX
Bikes: 1990 Romic Reynolds 531 custom build, Merlin Works CR Ti custom build, super light Workswell 066 custom build
OP, the failure of your embodiment of the BB model after seven years does not discredit the part in any way. It is the same as saying you drank a quart of whiskey twice a day and lived to be 110 or you never ate a gram of fat and died of a heart attack at 25 years old. So what. Is that the mean result expected? I don't think so. Unless you know the average usable lifetime of the particular part and its comparable competition (earlier, later, contemporary) and their standard deviations, you cannot derive any conclusion about its design integrity or manufacturing quality. Blow off steam if you must, but know it is just anecdote, among the least reliable of all data types.
In a broader sense the preoccupation of many on this forum with eternal longevity of their bicycles is ludicrous as is taking the failure of a bike part or wheel or frame as a personal affront. Everything wears out, some things sooner, some later. Some newer bicycle and bike parts designs emphasize other attributes like weight, aerodynamics, stiffness, etc. at the expense of longevity. That may or may not be what you want, but it is certainly neither evil nor a conspiracy against you and all other right thinking consumers. If you really think you will be happier with an obsolete square taper BB and compatible crank that you haven't already owned for 25 years or so, just go for it. I'm sure you will be able to find one somewhere. Personally I'm happy to have the modern developments. If some designs don't work out as I expect they should, well...(shrug)...that's life. As a good friend of mine says, "Hey, it ain't a kidney."
In a broader sense the preoccupation of many on this forum with eternal longevity of their bicycles is ludicrous as is taking the failure of a bike part or wheel or frame as a personal affront. Everything wears out, some things sooner, some later. Some newer bicycle and bike parts designs emphasize other attributes like weight, aerodynamics, stiffness, etc. at the expense of longevity. That may or may not be what you want, but it is certainly neither evil nor a conspiracy against you and all other right thinking consumers. If you really think you will be happier with an obsolete square taper BB and compatible crank that you haven't already owned for 25 years or so, just go for it. I'm sure you will be able to find one somewhere. Personally I'm happy to have the modern developments. If some designs don't work out as I expect they should, well...(shrug)...that's life. As a good friend of mine says, "Hey, it ain't a kidney."
#12
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Joined: Dec 2009
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From: Houston, TX
Bikes: 1990 Romic Reynolds 531 custom build, Merlin Works CR Ti custom build, super light Workswell 066 custom build
Lighter? A Shimano 600 crank from 20 years ago weighs about 600 grams - add in 300 grams for a square taper BB and the weight isn't that far off a modern crank - a new Ultegra double and BB combo weighs 960 grams. As for stiffer, the small amount of torsional bending in the spindle isn't worth mentioning, and the external cups don't do a thing for lateral deflection anyway.
#13
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From: Ogden, Utah
Bikes: CAAD 10, Cervelo P2 SL, Focus RG-700, Quintana Roo #101
Lighter? A Shimano 600 crank from 20 years ago weighs about 600 grams - add in 300 grams for a square taper BB and the weight isn't that far off a modern crank - a new Ultegra double and BB combo weighs 960 grams. As for stiffer, the small amount of torsional bending in the spindle isn't worth mentioning, and the external cups don't do a thing for lateral deflection anyway.
#14
▒▒▒▒▒▒

Joined: Jan 2004
Posts: 476
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From: New York
The larger spindle DOES make a substantial difference in stiffness, and makes installation much easier. As does the wider bearing stance. Then again I have snapped a couple cartridge BB spindles, so maybe I'm a freak. I would suspect that the larger external cup BB bearings would last longer, but haven't seen data to back that up. I will say that it's silly you can't service external BBs more easily, and that OEMs advocate that you toss them if there's a problem.
#15
It is not that I obsess over the longevity of my bike. I just marvel over it and love the idea that in today's world of expendable consumer goods I own something that has lasted so long and performed so well. Sooner or later I will need to buy a new bike. It will be interesting to see if I get 20+ years out of it.
#16
pan y agua

Joined: Aug 2005
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From: Jacksonville
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Difference is that square taper BB's are much more prone to coming loose. The reason octalink was developed, and now 2 piece cranksets was that the square taper interface isn't as good at holding a crankset together.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
#17
Like there were never any problems with Square taper cranks. Aluminum crank arms will fail over time where the arm attaches to the steel spindle, with the hole in the crank arm enlarging, particularly if the crank is ridden with the fixing bolt just a bit loose.
Old square taper internal BB's had an advantage with friction, over modern external sealed bearing bb's, but I don't think many people would maintain that square taper is a superior interface for attaching a crank arm to a bb spindle.
Old square taper internal BB's had an advantage with friction, over modern external sealed bearing bb's, but I don't think many people would maintain that square taper is a superior interface for attaching a crank arm to a bb spindle.
Back on track. Agree with Merlin again.

Square taper in my opinion is pretty flawed. But BB30 which I believe you will see evolve toward PF30 with collet BB in the next five years...former is flawed as well. I believe sweet spot still is threaded BB with external bearing crank aka DuraAce or Campy Record UT. Pick one.
#18
Exactly. Octalink which was a stepping stone to 2 piece outboard bearing cranks offered greater surface area interface for more robust crank arm/spider attachment compared to square taper. It can still be argued what is better today...Shimano's dual pinch bolt crank arm attachment which is excellent versus more common industry splined hard shoulder end bolt attachment which is solid as well. Thankfully square taper is gone. A hard shoulder is much more secure than a tapered square or spline which even changes chainline and Q-factor due to mating spline tolerance stack up.
Last edited by Campag4life; 07-24-13 at 07:13 AM.
#19
Descends like a rock
Joined: Oct 2010
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From: Fort Worth, TX
Bikes: Scott Foil, Surly Pacer
Its pretty simple - we've traded some longevity for lighter weight. If you prefer the old school, really long lasting stuff, its still out there.
https://store.velo-orange.com/index.p...cranksets.html
https://store.velo-orange.com/index.p...cranksets.html
#20
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Joined: Jul 2011
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From: Merry Land
Bikes: Guru Evolo R, Colnago Pista, Look AL 464P SS, various frankenbikes
+1
Square taper in my opinion is pretty flawed. But BB30 which I believe you will see evolve toward PF30 with collet BB in the next five years...former is flawed as well. I believe sweet spot still is threaded BB with external bearing crank aka DuraAce or Campy Record UT. Pick one.
Square taper in my opinion is pretty flawed. But BB30 which I believe you will see evolve toward PF30 with collet BB in the next five years...former is flawed as well. I believe sweet spot still is threaded BB with external bearing crank aka DuraAce or Campy Record UT. Pick one.
Last edited by stilltooslow; 07-24-13 at 07:26 AM.
#21
Interesting. They need to work on the finishing a little. Self extractors are a pet peeve of mine. Great concept for a problem that did not exist. Crank arm extractors are a great tool and one of the more satisfying ones to use, especially when you feel the crank arm release from the spindle. With self extracting bolts, it asks too much of the hex wrench to loosen a tight bolt. Most of the time they work, but if they don't it can get ugly.
#22
because most use press aka interference fits throughout. They do have their place and without them, we would have many gas engines on the planet. 
But you are quite right and Praxis is what I was referring to implicitly in my post. I believe their BB is the future. BB30 is needless and costly to manufacture due to insert molding and/or finishing machining of cup bores. PF30 is a single molded in 46.0mm hole. Shift the complexity to the BB...which isn't much complexity by comparison. The Praxis BB is simple, effective and elegant and more importantly unlike BB30...non invasive. What I meant by the next 5 years is...a collet BB will be much more the norm and likely adopted by OE bike companies and not just the aftermarket...provided they can work around the patent infringement.
Last edited by Campag4life; 07-24-13 at 08:33 AM.
#23
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From: Merry Land
Bikes: Guru Evolo R, Colnago Pista, Look AL 464P SS, various frankenbikes
Yeah, I know that, but I was really referring to their use on bikes. Even there, they do work pretty well in some places such as sealed bearing hubs. But for an old 'ball and cone' guy like myself, there's nothing like threads to give one confidence in a stable, creak-free fit.
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