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Old 06-23-07, 08:05 AM   #1
man of calibre
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You know your middle aged when...

I am finding myself increasingly despairing about the componentry on the latest machines lined up in bike shops. Most of the features on these bikes seem so unnecessary and counterproductive. Is this the onset of middle age?

As an example, there are two main bearings on a cycle that take a lot of force and weight: the headset and the bottom bracket. Manufacturers are now telling us that the best way to design headsets is to build the bearings inside the head tube in order to reduce 'stack height' and build a clean looking front on the bike, this design requires a new frame to take the bearings. This is fair enough, although I think the stack height has the benefit of disguising the height I have set my handlebars!

So it stands to reason that if headsets are improved by putting the bearings inside, bottom brackets should be pretty close to the optimum design because the bearings are already internal. Wrong! We are now supposed to accept as given that putting the bearings on the outside will make a better design.

My ISIS bracket gave out after a year so I would consider the Truvativ ISIS Overdrive brackets with oversize shells be a pragmatic solution to known flaws in the ISIS design. It builds on established technology and hides the mechanical parts inside the shell where they belong. But - surprise surprise - Truvativ have jumped onto the external bottom bracket bandwagon. This is with a design of their own which I understand to be completely incompatible with anybody else's. They have, AFAIK, stopped marketing the Overdirve design. Not that they tried that hard in the first place - if the idea was to use the MTB market as a beachead into cycling as a whole they should have offered it in shell widths between 68 and 100mm - something like the 83mm standard that is popular on downhill MTB.

So what happened is that Overdrive - a logical progression built on an open standard - ISIS, and backward compatible with the latter - has been abandoned in favour of a fragmented approach with every manufacturer using an incompatible external bottom bracket design of their own.

I think the external bearings have a place: as a retrofit to older bikes. If the forces on the BB demand a bigger shell they should design the frame around the newer, better standard. Manufacturers are having to change their frames in order to have a new model every year and to accomodate different headsets and axle standards in any case which sinks the argument that everything needs to be backwards compatible. If having bearings on the exterior of the frame gives real advantages then why are manufacturers building internal bearing headsets?

So there you have it - one of the things that make me feel decidedly old and cynical about the cycle industry and more specifically its marketing. I am starting as a consequence to spend a lot of time on the Rivendell Bicycle Works website!

Does anybody else have examples of 'progress' in bike design that makes you think 'hang on a minute - is it really just me or are we all being led up the garden path?'...

Oh yes, and you know middle age has been reached when you write a long post about a bicycle component that very few people even consider...
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Old 06-23-07, 08:14 AM   #2
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I thought buying a sports car was the middle age thing to do?
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Old 06-23-07, 08:29 AM   #3
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You're missing a few basic concepts:

With integrated headsets, the headtube is made larger so that the same size or larger bearings and bearing diameter of standard headsets can be used.. so this time there are fewer components to press, machine, etc. And the headtube takes the force, which I would think is stronger, or at least stiffer. Really, with integrated headsets, the main factor is that they're much cheaper to produce.

External bottom brackets.. combine three previously unavailable benefits. The first is the spindle. A tube of a slightly larger diameter will have about the same strength as a solid cylinder that's slighly smaller, but with less weight. To accomodate this tube, bigger bearings have to be used, and a bigger diameter bearing circle. Bigger bearings also provide the benefit of being longer wearing and smoother. But the standard diameter bottom bracket shells couldn't accomodate the bearings, so they moved them outboard, which provides extra benefit in that the larger area that's supported by the bearings, the stiffer and stronger the setup.

Sure, one could elongate the BB shell and make the diameter bigger, but to keep the shell machining costs where they are, it'd need to be threaded in the same way that they are now, which would put the bearings right under the threads, which would mean still a larger diameter. And one would need to find a way to bring the cranks right up next to the bearings so that the bearings support as much area as they can. And I assume there are some disadvantages to larger BB shells..

Backwards compatability is long gone in the bicycle market, my friend.
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Old 06-23-07, 08:32 AM   #4
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They change things to make you think your bike is old and outdated. Don't fall for it. All of the old stuff works just as well or better than the new stuff, at least in terms of HS and BB.
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Old 06-23-07, 09:01 AM   #5
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Quote:
Originally Posted by man of calibre
So it stands to reason that if headsets are improved by putting the bearings inside, bottom brackets should be pretty close to the optimum design because the bearings are already internal. Wrong! We are now supposed to accept as given that putting the bearings on the outside will make a better design.
Uhhh... no. BBs and headsets withstand very different sets of forces. Headset force is mostly compressive; BB force is mostly sheering.

There are several reasons for external bearings. In sheer the bearings form the fulcrums in a class three lever. The farther apart the fulcrums (assuming equal lever arm length), the less the load on each. In addition, the farther apart the bearings the less any play in the bearings appears at the pedal. And if that's not enough, external bearings aren't restricted by the diameter of the hanger tube. Larger bearing allows larger axle which can be stronger and roll easier, and longer races wear better.

Btw, if you think that headsets are standardized, think again. Headset "standards".
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Old 06-23-07, 09:31 AM   #6
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Things change, that's a given. Sometimes for the better, sometimes for the worse and sometimes just for the sake of change.

If we followed Grant Peterson's advice we'd be riding 26 pound steel lugged frames with 5-speed freewheels, steel cottered cranks and downtube friction shifters. BTW, all of those items were "revolutionary" at one time and the Grant Petersons of that day decried them as unnecessary too.

As to the specifics of your posting, the "integrated" headset has by no means become universaal and some manufacturers that adopted them have gone back to the former press-in cup type. Litespeed is a notable example.

And yes, your thinking is a sign of advancing age. Welcome to the club!
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Old 06-23-07, 09:36 AM   #7
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Quote:
Originally Posted by bsyptak
They change things to make you think your bike is old and outdated. Don't fall for it. All of the old stuff works just as well or better than the new stuff, at least in terms of HS and BB.
Hear, hear, for example, old school cup/cone BBs and headsets, real good ones like Campy Record.

How did this idea that BBs should be replaced every year or so get started anyway?


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Old 06-23-07, 09:52 AM   #8
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How did this idea that BBs should be replaced every year or so get started anyway?
ISIS.
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Old 06-23-07, 12:22 PM   #9
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I've been thinking that way for a long time and I'm only 22. I rode a bike I bought for 300 bucks coast to coast and I didn't even break a spoke. Alas, for the majority of biking stuff, durability is what needed (not light weight stuff). Carbon fiber/titanium is great when your in a race, but I'll take an old school steel frame (or my current Al frame) any day of the week. Ever notice that people are still riding those old Schwinns around from the 70s? Its cause they are built to last. But that doesn't provide the bread and butter income bike shops need. Never the less, good older bikes can be found. I think that you only really need the newer advancements (anything thats come out after 90) if you are into racing, you actually mountain bike, or you ride in the rain and need disc brakes. Other than that, I'll stick to my cantilever brakes and threaded headsets. I may be seen as odd, but it works.
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Old 06-23-07, 12:30 PM   #10
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Guess what, your wish is coming true! Trek is widening the bottom bracket on its newest machine.
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Old 06-23-07, 12:59 PM   #11
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Say what!
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Guess what, your wish is coming true! Trek is widening the bottom bracket on its newest machine.
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Old 06-23-07, 02:57 PM   #12
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Say what!
90mm BB shell
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Old 06-23-07, 03:52 PM   #13
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Geez! Maybe the cranks will have a reverse flair.
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Old 06-23-07, 04:04 PM   #14
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You do have the most telling sign of the onset of middle age; Gratuitous grumpiness. You need to be careful, or grumpiness will become a habit. Then other people will just think you're always grumpy. To fight it, you have to learn to let go of a lot of things. Keeping this in mind has helped; If they are not calling you for solutions, it's because you aren't supposed to be worrying about it. It has been assigned to someone else. So, let it go. bk
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Old 06-23-07, 05:09 PM   #15
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You need a nap after a ride.
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Old 06-23-07, 11:34 PM   #16
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Well I'm approaching dotage and find that I can pass right by those gadget-component-loaded bikes lined up in the LBS with about the same amount of interest I'd have for the bike display rack in WalMart. Perhaps OP needs something to despair about in which case the market-driven technical changes in bikes is as good as anything else. I would suggest tho that in maybe a decade or so OP won't care either.

I know an old railfan in Iowa who delights in baiting the young technocrats in that hobby by saying, "Railfanning is serious business." One could substitute any hobby there for railfanning and have the same effect.
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Old 06-24-07, 01:26 AM   #17
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Quote:
Originally Posted by Boss Moniker
You're missing a few basic concepts:

With integrated headsets, the headtube is made larger so that the same size or larger bearings and bearing diameter of standard headsets can be used.. so this time there are fewer components to press, machine, etc. And the headtube takes the force, which I would think is stronger, or at least stiffer. Really, with integrated headsets, the main factor is that they're much cheaper to produce.

External bottom brackets.. combine three previously unavailable benefits. The first is the spindle. A tube of a slightly larger diameter will have about the same strength as a solid cylinder that's slighly smaller, but with less weight. To accomodate this tube, bigger bearings have to be used, and a bigger diameter bearing circle. Bigger bearings also provide the benefit of being longer wearing and smoother. But the standard diameter bottom bracket shells couldn't accomodate the bearings, so they moved them outboard, which provides extra benefit in that the larger area that's supported by the bearings, the stiffer and stronger the setup.

Sure, one could elongate the BB shell and make the diameter bigger, but to keep the shell machining costs where they are, it'd need to be threaded in the same way that they are now, which would put the bearings right under the threads, which would mean still a larger diameter. And one would need to find a way to bring the cranks right up next to the bearings so that the bearings support as much area as they can. And I assume there are some disadvantages to larger BB shells..
yeah, well, while this all may be true, the fact is, there is not much wrong with the good-old square-taper. Yeah, it's maybe 12 micrograms heavier than a splined interface. Boo-hoo. I have yet to meet an ISIS user who is satisfied with the durability of their BB - or at least, that will say their ISIS BB lasts as long as a ST BB, external bearings or not.

This is all crap, all this 10-speed tiny-ass chains and cassettes and shifters that cost you your monthly salary (and last less than the older stuff), and all the splined interfaces, that require newcranksets... all crap to force you to repurchase the stuff that already works, and works well. Screw the industry. They pull the same **** with the SACD (super audio CD) to make you repurchase your songs on a new format. Or HD-DVD. Or what about the various director's cut, ultimate, expanded, alternative ending ETC ETC ETC re-releases of the same movie - again, just so they can dip their dirty hands in your pockets.

Well, the bike industry is pulling the same crap. And people are faling for it, sadly.



Quote:
Originally Posted by Boss Moniker
Backwards compatability is long gone in the bicycle market, my friend.
Well, that's what they want, but I can still buy ST BBs. I do have trouble finding 110 mm BCD 1/8" chainrings, though. Damn.

Last edited by wroomwroomoops; 06-24-07 at 01:46 AM.
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Old 06-24-07, 07:47 AM   #18
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Guess what, your wish is coming true! Trek is widening the bottom bracket on its newest machine.
According to the Trek spiel the headset and bottom bracket are both integrated into the frame. Integrated headsets have limited life before they wear out the frame which is then junk. With this new Trek frame there are two sets of integrated bearings, either of which would eventually become loose in the frame, wrecking the latter. So now there are two points of failure. great.

I quote from the Trek website:
Quote:
The all-new Madone changes the rules with a no-constraint, total-performance system.
  • The 68mm bottom bracket standard was in the way of a more efficient drivetrain, so the Madone integrates a 90mm bottom bracket.
  • The 1-1/8 inch lower headset diameter was in the way of a better fork, so the new Madone launches the E2 1.5” fork and headtube
Personally, if I were designing a 'total performance system' from a clean sheet of paper, the first thing I would have done is to decide whether I was going to use millimeters or inches. To be fair, at least the bike represents the state of the art in its time, and as the frame will have a limited life anyhow it does not need to be backwards compatible.

The thing that was really winding me up was that a lot of new bikes will not be backwards compatible with the stuff you already have but still retain old standards in some instances - these being interface points with parts of the groupset. This is done not with the intention of being backwards compatible with all the bits you already have, but rather so that we can buy the latest groupset each year. This latest groupset will of course claim to address the issues that could have been resolved by a fresh look at the basic standards upon which bikes are built.
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Old 06-24-07, 10:48 AM   #19
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Personally, if I were designing a 'total performance system' from a clean sheet of paper, the first thing I would have done is to decide whether I was going to use millimeters or inches. To be fair, at least the bike represents the state of the art in its time, and as the frame will have a limited life anyhow it does not need to be backwards compatible.... This latest groupset will of course claim to address the issues that could have been resolved by a fresh look at the basic standards upon which bikes are built.
Amen. See my post here.
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Old 06-24-07, 11:04 AM   #20
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Personally, if I were designing a 'total performance system' from a clean sheet of paper, the first thing I would have done is to decide whether I was going to use millimeters or inches. To be fair, at least the bike represents the state of the art in its time, and as the frame will have a limited life anyhow it does not need to be backwards compatible.
You must be French at heart. Look at the older, now disregarded French bicyle - the only non-metric they succumbed to was the 1 3/16" ID on the head tube (even Japan tried 30mm there and folded). The Italians are really screwy. What in the world is a BB threaded 36mm * 24 tp inch? Of course we all use a RD hanger that's threaded 10mm * 26 tp inch? Bicycle measurements are insane
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Old 06-24-07, 01:38 PM   #21
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Quote:
Originally Posted by vpiuva
Bicycle measurements are insane
Bicycle "standards", such as they are, were developed by both the British and the Continental Europeans and the resuls are a wierd mix of both English and Metric units. There is no way they are going to be rationalized without making even more stuff obsolete than already is.

BTW, why was the new "Oversize" handlebar standard defined as 1-1/4" (31.75 mm, aka 31.8 or 31.7 mm depending on the bar manufacturer.) Why not 31.0 or 32.0 mm? I believe this size was first standardized in either Europe of Japan.
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Old 06-24-07, 08:27 PM   #22
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I thought middle age was when you thought the T-shirt with the King of the Hill guy on a lawn tractor that says "Party like it's 1999.95" was cool.
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Old 06-25-07, 07:49 AM   #23
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I’ve simply succumbed to the fact that I must: 1) do my own homework/analysis based upon actual assembly and riding experience (i.e., trial/error), and 2) purchase components via the web from small/mid-sized companies that share my belief of using ‘low-tech/high-quality’ parts (e.g., Phil Wood, Chris King, Paul Components, White Industries, etc).
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Old 06-25-07, 08:04 AM   #24
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2) purchase components via the web from small/mid-sized companies that share my belief of using ‘low-tech/high-quality’ parts (e.g., Phil Wood, Chris King, Paul Components, White Industries, etc).
I'm not sure Chris King, etc. would appreciate being called "low-tech". The quality is high but the prices are absurdly high.
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Old 06-25-07, 08:37 AM   #25
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The quality is high but the prices are absurdly high.
+1
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