Tuesday, March 10, 2015

More Press-Fit Bottom Bracket Madness

Back in 2013, I wrote about press-fit bottom brackets, and all the various "standards" that have been introduced in recent years. I summarized it by saying essentially that the only thing "standard" about bottom brackets today is the creaking. Not surprisingly the creaking continues. What IS surprising to me is that the industry has gone almost two years without introducing yet another new bottom bracket "standard."

Several companies think they have the solution to creaking press-fit bottom brackets, and they want you to spend a lot of money attending to something that should never have been an issue on a $4000+ carbon fiber w√ľnderbike to begin with.

One of these solutions is the BBInfinite. Funded on Kickstarter last summer, the BBInfinite is supposed to eliminate the variables in tolerances between the bottom bracket shell of the frame and the bearing mechanism by putting both the left and right side bearings into one complete shell, and the whole shebang is pressed into place as one single unit.

The BBInfinite sells for $165, and it does come with tool adapters for Park headset presses. Removal takes more special tools, including an air hammer (!) and those tools are sold separately. Some users will probably want to buy the tools anyhow, though I wouldn't recommend doing the job at home.


Remember when these were all the tools you needed to install, remove, or service a bottom bracket and crank? And keep in mind that two of those spanners also service headsets. The one on the top also installs/removes pedals.

The installation video for the BBInfinite shows all of these tools to install the unit -- though I think the main one needed would be the Park headset press and the special adapters or inserts for the press. Given the very specific nature of some of the tools (made solely for the BBInfinite) and the immense possibility of destroying a very expensive carbon fiber frame should something go wrong, I think few home mechanics will be doing the job themselves.

No grease or oil. Everything must be clean and wiped down and decontaminated with alcohol. Only in the final stage of the press-fit process does one apply a bit of loctite -- because loctite is like the "take two aspirin and call me in the morning" solution for press-fit bottom brackets. 

They say it goes in fairly easy with a headset press and some special adapters, but it hurts just to watch it. I think the potential for destroying a carbon fiber frame would be great, so I wouldn't recommend trying this at home, kids.

To remove the BBInfinite, you need an air hammer and their own special bearing dies. The video also notes "Make sure removal of the module is necessary before commencing" Why? I'm guessing the BBInfinite is not meant to be installed or removed more than one or two times in its lifespan.

An instructional video on YouTube shows how to remove the BBInfinite with the air hammer -- good thing they remove the sound from the video. "Eye and hearing protection are recommended." Luckily this isn't something that needs to be done often. I guess the makers are pretty confident that once installed, it shouldn't need to come out again. Should the bearings need to be serviced (well, not serviced, exactly - I should more correctly say "replaced") it is possible to do it without removing the entire BBInfinite unit - but that job requires yet another special set of tools (not shown).
Now, the whole point in creating something like the BBInfinite is to try to eliminate some of the fit issues that come from inconsistent tolerances between the frames and the components. It seems like a good system in that the left and right bearing units will always remain in parallel with one another -- which may not be true of units that are pressed in separately from each side of the frame. But it seems to me that if the tolerances of the frame are off enough from those of the bottom bracket unit (even this one) it could still have problems with creaking. And on the company website, there are two posts headed up with something like "It still creaks." For example, "I installed a BBInfinite module and my bike is still creaking. What do I do now?" Various culprits are then named, from cranks to wheels, to cracks in the frame. Great.


Another new entry into the Stop-My-BB-From-Creaking foray comes from Enduro. Called the TorqTite, it uses an innovative new method to eliminate persistent creaking. It threads together. That's right --- the solution to press-fit bottom bracket fit issues is to install a threaded bottom bracket. When the two sides are threaded together and tightened down, the frame is then essentially "clamped" tightly between the cup flanges to eliminate any movement that would then lead to creaking. It's like the next logical step in the evolution of press-fit bottom brackets. My prediction is that the next step is that someone will suggest cutting threads into the frame's bottom bracket shell to match up with the threading in the BB unit -- thereby giving a uniquely sure-fit, fool-proof solution.

Proponents of press-fit bottom brackets like to point out that headset cups have been press-fit into frames practically forever with no issues. To that I point out the obvious, that being that headsets are subjected to totally different kinds of forces than bottom brackets. Others will remind us that old-style American one-piece cranks, like those found on old cruisers, department store bikes, and on BMX bikes, have always used press-fit bearing cups without problems. Yes, that's also true -- so then what does that say about the state of the industry today that their manufacturing tolerances aren't even as good as those used on bottom-level bikes from the past? Proponents also love to talk about the increased stiffness in today's bottom brackets. To that I reply, just how stiff do bottom brackets need to be? Once things moved from the old square-taper bottom bracket spindles (typically about 17 mm in diameter), to the external-threaded cups with their 24 mm spindles, it seems to me that bottom brackets got as stiff as they'll ever need to be. Nobody can feel the difference, despite what the manufacturers proclaim in their ads.

Nope - I've said it before, but I'll say it again. The only real reason for going to these press-fit bottom brackets is to save time and money for manufacturers. No metal sleeves to be bonded into their popped-out-of-a-mold-somewhere-in-asia frames. No machining to precise tolerances. No threads to be cut. And it's apparently left up to various frame makers and component makers to come up with their own tolerance specs.

If somebody has a modern carbon fiber w√ľnderbike with bottom bracket creaking issues, one of these two new products might offer viable solutions. But wouldn't it just be better if the industry picked itself a standard, and eliminated some of the tolerance variables? I think high-end bicycle buyers need to start demanding better.

On BikeRadar, I saw this recent rant from AngryAsian where he points out that "frame warranties almost always include a clause that covers 'manufacturing defects'." Therefore, if a person's frame is not made to the proper specifications for the intended bottom bracket system, then they should demand replacement. "You're sitting on a lemon - and no amount of sugar is going to make it taste good. . . Demand a correctly made version of what you bought. If the shell dimensions really aren't what they should be, your bike is defective and you're entitled to one that isn't." Maybe he's right. If people kept coming back to the manufacturers demanding replacement, instead of trying one "sure-fire" fix after another to solve the problems, something might actually done about it.

In the meantime, I'm quite happy riding along in silence on my steel framed bikes and their traditional threaded bottom brackets.

7 comments:

  1. For real space age technology check out Gokiso bottom brackets, just be prepared to pick your jaw up off the floor when you see the price. These guys even have a video on youtube showing a bike with a BB powering along at motorcycle speeds for literally thousands of hours.

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  2. Sorry got ahead of myself there, the hubs are out and available .The bottom brackets are still in testing phase, but you can have their wheels with their hubs, just don't plan on taking any holidays for a few years.

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  3. If the bearings in that first thing are even remotely decent, then I can imagine that most users will never need to remove them... as they could probably outlast the plastic bike that they're pressed into.


    There's a long stretch of path down here that the roadies like to use, and you wouldn't believe the concert of cracks and creaks and pops and bangs as their herd of plastic bikes zoom by. I would be enraged if my multi-thousand dollar bike made that kind of racket. Not that I have a multi-thousand dollar bike, just a bunch of several-hundred dollar ones that are a lot quieter and cheaper/easier to service myself with fairly inexpensive tools that work across the entire stable. Usually the only thing creaking on my bikes is my joints.


    Wolf.

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  4. I've used air hammers before, FOR BREAKING APART METAL. There's no way people aren't going to shatter plastic BB shells with this nonsense. If I were a bike shop, I wouldn't touch those things with a 10 foot pole.


    Wolf.

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    1. certainly, if one used the air hammer, it's unlikely they'd be re-using the bearings -- that's for sure. I think the risk of damaging the frame would be high, so I wouldn't want to mess with it. I'm sure the idea here is that once it's installed, one wouldn't be removing it. If it really works, I guess there'd be no reason to (?).

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  5. Stuff like the Enduro reminds me of those doctors who give patients drugs to counteract the side-effects of other drugs they've prescribed and, in doing so, create other side-effects in need of more drugs.

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    1. I think that's where the madness comes into play. Bottom brackets, headsets, now hubs. And carbon fiber rims. It goes on and on.

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