"" The problem with square taper bottom bracket is that the bearings wear-out faster than a cup unit BB. ""

say fucking WHAT ??

good lord, where to begin . . . . . .

Damn Ted, 4 broken chains in one season! That is crazy. What kind of riding are you doing on that transit bike?

dude. how long have you ridden bikes?

i have campy square taper bb's that are over 25 years old, that are as smooth as the day they were made. a couple phil's like that, also. you gonna tell me a modern outboard bb is gonna do that? they are doing good it they make it thru the rainy season, so far.

c'mon man. this is nuts.

P.S.

try installing your chain correctly.

maybe you could describe how climbing a hill on a singlespeed would cause an axle to break, too . . . . . . . on second thought, please don't.

You sound like you've got a bad case of "Weight-weenieitis"

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I'm not trying to take sides here on the campy vs shimano debate, but boy, where to start:

"The large chain ring on tri crankset goes deeper into the crank, kind of like the deep dish wheels from HED, definitely reducing drag"
Aerodynamic claims can rarely be made purely on what looks like it'll be aerodynamic. This is one of my pet peeves about all the aerodynamic claims people make without windtunnel numbers to back it up. Plus who knows what happens with your feet spinning around causing all sorts of turbulence. I'd be willing to bet that the chainrings make about negative zero difference in aerodynamic drag.

"The problem with square taper bottom bracket is that the bearings wear-out faster than a cup unit BB... Another problem with square-taper BB is that it stretches quite easily" Well built bottom brackets with free bearings can last a reallly really really really long time. And as for stretching, only if you overtorque the crank bolts or do something else along those lines... And if it were such a bad system I dont think it would have been around so long.

Also, when comparing weight of the crankset and BB, I think you need to compare the BB and crankset weights added together, not as separate parts.

I'm not aware the campy made titanium brake calipers... I'm pretty sure they are anodized aluminum with ti hardware.

"For sure the carbon fiber is way stiffer than the aluminum" I think you'd have to test this to make this claim.

And how the heck have you broken 4 chains? thats insane.

Um, the only difference between standard BB (ie square taper, octallink, ISIS) and the outboard BB (ie FSA mega EXO, DA10) is that the bearings are moved outwards a bit, and they can use slightly larger bearings. Both systems have axels and bearings.

Well built square taper BB, like Phil Woods and others, can last a really long time. Durability often comes down to good bearings with excellent seals, tight tolerances, and faced/chased BB shells. Thats how Chris King in the hub and headset business made a name for themselves as being bombproof.

Dude, Man i just dont know where to start, but here goes.

The S cranks are the same, only the chainrings are different and the teeth (chainline) line up the same on both.

The reason square taper BB may wear faster is because the bearing Diam is smaller, they both have axles. Also the main difference is life is bearing sealing. Poorly sealed bearings will wear quickly on both systems. From a wear standpoint campys are fine, most lasting longer than shimanos system has been available.

Some of the bolts on a campy brake are Ti. the actual arms of both C and S are aluminum, not Ti. Both C and S work fine and a ham fisted operator can skid either front or back.



Styrrell

Ted,

this is quite possibly the most absurd gear post ever on Slowtwitch. I don't even know where to begin. You have absolutely no idea what you are talking about...

Some highlights...

- External BB sets were developed by Shimano and others primarily to compensate for the fact that the bearings on Octalink and Isis BB's have nowhere near the lifespan of those on square taper BBs. No one - and I mean no one - has EVER had a gripe with bearing durability on good st BBs. Your attempt at explaining the bending forces applied to a bb is, well, ridiculous. The forces applied to a BB spindle do not even roughly correspond to the example you present, and square taper BBs ARE NOT MADE OF ALUMINUM.

- Campy brakes are NOT titanium. Record brakes have titanium fitments, but the caliper bodies are forged/machined aluminum.

- "Breaks," for this particular meaning, is spelled "brakes."

- "Aero" Shimano chainrings? What are you smoking? The reason Shimano offers a "Tri" crankset is that they use a different shift ramp pattern for the larger chainrings.

- Rusting steel cogs is a non issue. They are constantly lubricated and polished by the interface with the chain.

72 Grams. WITHOUT THE SPINDLE!

- "As similar of a metal steel is when compared to titanium (they ride the same), Titanium wins by 100% on the sickness factor scale. Not only is it a million times lighter (slight exageration) ..."

Oh - my - god.... I don't even need to respond to this...

- "I've broken like 4 chains this season alone on my single speed transit bike ..."

You need to fix your chainline, or switch to a chain that you can't install incorrectly, like a Sachs.



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Tech writer/support on this here site. FIST school instructor and certified bike fitter. Formerly at Diamondback Bikes, LeMond Fitness, FSA, TiCycles, etc.
Coaching and bike fit - http://source-e.net/ Cyclocross blog - https://crosssports.net/ BJJ instruction - https://ballardbjj.com/

Shimano crankset- the only difference between the FC-7800 and FC-7800Tri model is the sizing of the chainrings. "Standard" cranks have 50-53t big rings and 39-42t small rings. "Tri" cranksets have 54-56t big rings and 42-44t small rings. Shimano made aero rings for the 9-speed cranksets, but have yet to sell an aero version of the 10-speed cranks to the public (Lance and some others have been seen on prototypes). I have seen a few people use 9-speed aero rings on 10-speed cranksets; I doubt they shift well (but don't know for sure).

Bottom brackets. As others have said, square taper bb's have long been the standard for bicycles. There are crappy ones and good ones, as with most components. A good quality Campy or Phil Wood bottom bracket will last a very long time. You will not be changing them "every few months". Some say that Campy is living in the past with their square taper bb's, but you can't argue with what is proven and works. That being said, I do like the idea of larger bearings in the external systems, but would rather see the diameter of the bottom bracket shell increased instead (a la Cannondale, Pinarello, or the new Specialized cranksets. They had to make up their own bb's and shells since it isn't a standardized thing... FSA tried that but it never caught on).

Cassettes- I'm going to raise the weight weenie flag on this one. Yes, ti is very cool, but won't last as long as steel. This is why Campagnolo and others don't use ti for the smaller cogs (they wear out faster). Campy does sell a full-ti cassette, but it is more for rich weight weenies than anything else. Dura Ace and Record cassettes are indeed very nice, but most people go for their slightly heavier, but equally smooth-shifting Ultegra and Chorus counterparts.

Chains- if you've broken a lot of chains, they're probably not installed correctly. I recommend using Wipperman chains and their quick-link attachments. No fear of incorrect installation, easy to service, last long... but they do cost you a lot (at least for the stainless versions).

Brakes: Campagnolo calipers are forged aluminum. The Chorus calipers have steel hardware; Record has ti. The brakes themselves are not titanium. I feel that the biggest shortcoming in Campagnolo's brakes is their lack of a quick-release on the caliper (it's on the brake lever). What this means is that when you use a time trial brake lever (or anything that isn't a Campagnolo Ergopower lever), you have no quick release for the brakes and must let air out of your tire to remove the wheel. I vote for Dura Ace.

Front derailleur: "For sure the carbon fiber is way stiffer than the aluminum." Are you really certain? Both Record and Dura Ace shift well, but I have actually found the Shimano to shift better. This also probably has to do with their chainring design and its ramps/shift pins. The carbon is very cool, but I would worry somewhat about its long term durability. As for the weight difference, it is negligible.


Keep in mind with this "frankenstein bike" the issue of component compatibility. For example, you can't use Campy shifters with Shimano rear derailleurs. Will this be a road or tri bike? If it's road, then the deciding factor may be which brake/shift levers you prefer. If it's tri, you really can't tell much of a difference between Shimano and Campagnolo bar-end shifters. After owning both Shimano and Campy road and tri bikes, I prefer Shimano for triathlon and Campy for road. If money is a big factor, then your best choice BY FAR is Ultegra. If money is no object, make a list of pro's and con's with DA and Record. When it comes down to it, they'll both be very nice groups. Mix and match if you want, but be careful. I.e. Campy rear der needs a Campy cassette, which needs a Campy rear hub and Campy-width chain (be it actual Campy or Wipperman or whatever). Also, you'd be best served by a Campy crank (for proper distance between rings) which would also need a Campy square-taper bottom bracket. While you're at it you might as well get the calipers too to match the rest of your stuff.

"this is quite possibly the most absurd gear post ever on Slowtwitch"

I think your statement is just plain wrong. Let me correct it for you:

This IS the most absurd gear post EVER.

There, much better.

Howdy,

Pretty much agree with everything you said, except if you are bound and determined to mix and match shimano and campy shifters, cogs, wheels, rear deraillers their is a company who makes widgets which make virtually any combo compatible.



Styrrell

I guess Ted had enough and just deleted it. Kinda sad when you think about how much time he must have put in the original post in the first place. I'm still amazed though 4 broken chains!

Ya well, the time i spent trying to put that bike together it was worth it, now everything is fine on it. I just can't ride it as hard. I originally had bent the axels in the rear wheel, finally i bought a BMX axel to put in the rear wheel, it's still holding up.

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"The aspect of sport that you learn is that you have your good times and your bad times, but you share it with great people." - George Gregan

Do you have a powermeter? I would love to know how many watts you have to put out to break 4 chains in one year!

no not yet. When i go for vo2max testing at university of montreal i'll find out.

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"The aspect of sport that you learn is that you have your good times and your bad times, but you share it with great people." - George Gregan

Are you planning on breaking another chain during the test?

haha no, the chains i broke were old mtb chains i had. When I built my single speed bike I had to go through alot of old parts just to get something decent going.
I'll post a pic when i find my digital camera, but It wasn't anything rediculous. It was just when my axels would bend in the back wheel the chain would skip over and snap.
I'm sure bjorn has some interesting stories to tell about breaking chains.

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"The aspect of sport that you learn is that you have your good times and your bad times, but you share it with great people." - George Gregan