davidad

A poor design is a poor design. The reason Suntour and shimano went with the freehub design was to move the right side bearings outboard for reliability. Cassette or Freewheel Hubs by Jobst Brandt

fietsbob

The other approach was taken to Beef Up the freewheel axle diameter , That works too ..

My Loaded Tour Bike has made many long trips to Europe , Phil Wood's Freewheel rear hub was 100% reliable ..

FastJake

After reading stuff online about q-factor the path that many seem to go down is that narrower is better and narrowest is best. This is what I believed anyway. So I setup my 1972 Fuji fixed gear commuter with a 102mm (square taper, gasp!) bottom bracket and an old crank with flat arms for extremely narrow q-factor. My knees did not like it. I kept the BB but put a different crank on that has the arms flare out at the ends. It's about the same at a modern road crank and feels perfect.

My take-away from that experiment is that q-factor does matter, at least to some people, but narrowest is not necessarily best. Everyone is going to have a certain range they feel ok with. Now I want to put some long road rides on a modern MTB crankset to see if my legs can handle the wider q-factor offered by those. I would like a fat bike someday but am worried about the (potentially) huge q-factor on those to clear the giant tires.

FBinNY 

I might have said the same to you about reading posts, especially post No.45 where I showed by your own measurements that the right side Q-factor was unchanged between the two bikes. (I suggested 3x that you measure the right side Q-factors, but I guess you prefer not to).

Of course I don't know the Q-factors for various cranks, and what's more I don't care. My point from the very beginning was that BB width isn't the determining factor.

The minimum right Q-factor is determined by the 45mm or so chainline requirement, and both are determined by chainstay clearance, and crank arm thickness. It's easy, and has been for decades to build bikes with Q-factors as low as those minimums, if that's the goal, and narrowing the BB does nothing to change that.

BTW- since I didn't know, I decided to measure the Q-factor on my sq. taper, 68mm BB Chrous road bike from 2001. Right side Q-factor is 71mm, (outside face of arm to centerline) and the left the same, for a total of 142mm, which is lower than your "narrow" bike. There's plenty of room to bring the left in if I wanted to, but I prefer symmetry.

Bandera

Not I, over the winter I'm converting two road bikes to triple cranks. One steel frame, the other the last generation of threaded CF BB.
Should take half an hour to remove the old crankset/BB and install new on each w/ zero compatibility problems or adhesives.

Simple maintenance, low cost and a reliable supply of components into the future, as it has been since I've been riding.
That matters to me, I keep machines in service for decades.
Proprietary or one generation and obsolete "standards" are not acceptable to me.

Pressed BB is an answer to a question that I didn't/don't ask.

-Bandera

fietsbob

My Touring Bike build was in Eugene, and within a short distance to my friends at the Burly Tandem, Frame shop,

So I Built it up with what was Their stoker's BB shell, snap rings with an Oversize pair of sealed bearings in a Closed tube BB shell

Modified with a Zirk fitting Added to load the space between the bearings with Grease ..






By the way low Q is gained with the old square to the axle Straight crankarms . that are not mainstream anymore.

Hanebrink Big Bike used a jackshaft which is another shaft and Chain to go around fat ATV tires , but still use a Normal Crank on the primary Chain.

dabac

HuClose, but not quite.
Marketing has always HAD a voice. It's pretty much the definition of marketing - to make itself heard and noticed.
What seems to be happening more and more nowadays, is that engineering has become marketing's slave, tasked to provide marketing with something to talk ABOUT, whether it is merited or not.

I can, on occasion, notice flexy frames and sometimes wheels. But I've NEVER gotten off a bike thinking "man, that would have been a sweeter ride if only the cranks/BB had been a bit stiffer".

Ronno6

Interesting to note that outboard bearing bottom brackets ARE press fit bearing BB's.
Just that the bearings are pressed onto the holders (cups?), which are then threaded into the frame.

These bearings are replaceable, by the way. Ceramic and steel bearings are available for outboard bearing BB's.

ThermionicScott 

I'm confident that they will have worked all the bugs out of press-fit BBs by the time I adopt them.

FBinNY 

To me they're like Windows 7. An improvement best if leapfrogged over.

FastJake

I actually like Windows 7 a lot. But what's the leapfrog beyond press-fit BBs? Surely they can't come up with anything dumber and more of a pain to work on?

FBinNY 

You underestimate them.

In any case, I made a mistake. I actually do like windows 7, and was happy to have leapfrogged Vista. Now, like with bike progress, I was forced to move to Windows 8 when my laptop died, and have mixed feelings about it. In all honesty, though, I suspect my issues with 8.1 are more related to how comfortable I was with 7 than with actual issues with 8.1.

OTOH - as the owner/user of a number of business programs, I find it annoying that when I"m forced to upgrade the platform, I often have to shell out for updated versions of programs I already paid for.

Now windows 10 is coming, and if I should buy new hardware I might have to shell out for another round of program upgrades. In fact I still have an XP machine that I have to keep alive because there's stuff on it I either can't or won't pay to upgrade.

Sadly bikes are becoming this way. If you crash the frame, it can become a problem finding a replacement that will accept your sitll OK components.

JonathanGennick 

Yes. I hate that press-fit has taken away the easy of doing my own work.

I know you all have been talking about road bikes. My one press-fit bike however, is a mountain bike. Best thing I ever did was to buy a Praxis Cycles conversion bottom-bracket:

CONVERSION BB | Praxis Cycles

Beautiful! It screws in to a press-fit shell. Worth every penny to me not to have to muck about with actually pressing.

Santa Cruz, I noticed yesterday, continues to support the English threaded bottom-bracket, and in part they say it is because many of their customers are like me, building up their own frames at home.

ThermionicScott 

Heh, that's kind of what I was hinting at -- that by the time I can't get threaded square-taper parts anymore, who knows what'll be out there?

loimpact

Of course you know that if you're not using a bearing press (home made or otherwise) to pre-fit and a BB tool to remove it that you're actually doing it wrong, right?

https://www.youtube.com/watch?v=Eory8iw2BqU

FWIW, it's a 6 of one, half a dozen of another scenario for me. My first road bike was an SR 10-speed. It went a full year before the cranks gave me issues. (square taper) The cranks arms simply wouldn't stay tight. After several retightens w/ loctite and various other tricks, I gave up & sold the bike.

(shrug)

JonathanGennick 

Oh my! This is where I wish my memory was better, because I do it recall just what I did.

On the one hand, I am pretty careful about following install instructions for bike parts.

OTOH, it was three seasons ago, or maybe four, and I honestly do not recall doing that press-fit as described in the video.

OTOOH, I do know that the bike is the one for which I bought larger washers for my threaded rod. OTOOOH, those may have been to seat the tapered headset.

If I had to guess, I would guess that I followed the instructions and just do not remember well. Can't be sure though, because I don't remember.

akansaskid

OP here. The responses seem to run from "I feel your pain" to "You can learn to live with them". Not exactly a ringing endorsement of press-fit bottom brackets. I notice that Bikes Direct's Motobecanes still have threaded BBs. Sadly, I might have to consider them if I want a new bike.

HillRider

Yes, Campy has an inherently a poorer design but more than compensated for by the use of a larger diameter axle. The real criterium is "does it work reliably" and the answer is a resounding yes. I have over 30,000 miles on my 2006 Campy Chorus hubs and they are still in perfect shape and nothing has ever broken so I consider that a successful design. Unlike freewheels, particularly over 7-speed, where broken axles were a chronic problem due to the excessive unsupported axle length, these Campy hubs have avoided that completely with the larger axle.

loimpact

LMAO!!

And the memory problem doesn't get any better with age!

And I will say that the Praxis conversion kit is impressive, too. Though if Campag4Life visits this thread, he will enlighten a bit about the simplicity and dead-reliable potential of BB30 which I mostly believe to be true, minus riding in horrible weather, etc.

I still need to pull my BB30 apart to inspect. I found my cranks a smidge loose after I found a "tick" in mine and has been fairly quiet since I snugged it up, though still an occasional tick on the drive side whenever I really mash. I've got all the bearings, the loctite, the punch and just need to make my own press with a bolt, nuts & some washers. (Or just use a C-clamp & some wood) And then get 'er dun.

JonathanGennick 

It is true that I belong in the Over-50 forum.



They let me out every now and then though.

Batavus

Guys, the problem is not press fit BB's (eventhough I hate them with a vengeance, having worked on various press fit standards in a roadie shop).

The real problem is press fit BB's in conjunction with carbon fibre frames, especially the ones that have a monocoque construction.

The frame acts as a giant resonance-box, amplifying every tiny sound produced by all components and the friction between them. A rear wheel quick-release skewer left too loose can produce an almighty creak as if the crankset is about to explode. A seatpost not properly greased, under-torqued or over-torqued can sound as if the frame is about to break (but can be found easily by lifting your butt off the seat on a test ride.

Carbon fiber headset spacers need to be lightly lubed , because they can rub against eachother and start to squeak. Not to mention cables rattling against the liner inside the frame, etc etc. It goes on and on.

I am so glad I don't work in a roadie shop anymore, because I got quite sick of chasing creaks and squeaks, eventhough I got quite good at it.

The other problem is the tolerance the frame manufacturer uses for the BB shell. Aluminum shells can be chased and faced to accomodate slightly, but carbon ones cannot.

When new standards require tighter tolerances, frame mfgs and component mfgs need to up their game and produce something that is on a par with the dream they are selling. Instead they blame eachother for not adhering to the tolerances of the standard.

It's a ****ing nightmare and everyone in the business of selling these bikes keeps providing mitigating circumstances. It's hardly progress is it? More noise, shorter component life, rising maintenance costs.

Dealers can feel only half-blessed with selling more bearings and the like. I don't think any shop truly keeps track of the workshop hours spent on warranty squeak chases and component replacements.

HillRider

I think this is the heart of the problem. Frame makers don't adhere to adequate tolerance standards for their bottom bracket shell and most of the problems can be traced to this mis-match. Recently VeloNews' web site linked to a video by one of the techies from Art's Cyclery covering the various new bottom bracket "standards". His take was that almost all of the reported problems were due to sloppy manufacturing tolerances.

dr_lha

Nah, it's sh1t on Alloy frames too.

HillRider is on the money though. It's all to do with poor tolerances. That combined with crappy installs.

FastJake

The heart of the problem is frame makers replacing a perfectly good threaded system that's worked for... how long, 100 years? With a stupid press fit system. For what benefit? To save a few grams and make it "stiffer." I'm not going to buy the BS stiffness claims so I'm curious how many grams it actually saves since I'm occasionally a weight weenie.

HillRider

I'm not denying the various press-fit systems are the answer to a non-existent problem but, now that they are here and we seem to be stuck with them, at least they should be manufactured properly.

The weight saving has to be minimal and the "improved stiffness" claims have gotten to the absurd level everywhere on the bike, not just the bottom bracket