Prospective carbon road bike purchase - bottom brackets?

[MacMan]

Hello all.

Long time lurker.

I am seriously considering an investment in a road bike some time in the coming months. I have been shopping and missed out on a massively discounted Wilier Izoard XP recently because I really had nothing much to compare it to. In hindsight, I think it would have been ideal.

Anyway, that leaves the other offerings.

I wanted to consult the brains trust regarding bottom bracket types. Things have come a long way since the "revolutionary" sealed square drive BBs on my present MTBs. It would seem that just about every one of the modern designs has pluses and negatives. Just about every design has people complaining of interminable squeaking and pesky fitting issues. I like the idea of a threaded BB, but the majority of bikes seem to be going for press fit of some sort.

So, what are the real-world experiences here with press fit? Are they that bad? If so, how is it that the majority of manufacturers appear to be persevering with them because the frames are easier to manufacture.

General budget is for as little as necessary to get something with >105 components, wheels that won't succumb to having a 198cm 85kg clot on them. Pointers appreciated!

[Duck!]

Press-fit is extremely reliant on proper tolerances by the frame manufacturers to reduce the probability of noise. They can spin crap until they're blue in the face about all the supposed benefits, but it's a fundamentally flawed concept that only exists because it's cheaper and easier to produce.

[Tim]

So, what are the real-world experiences here with press fit?

Shimano press-fit in two Giant bikes no problems.
BB30 press-fit in two Cannondale bikes, failure. Creaking and cracking noises from near-new. One remedied with full refund the other had the bearing effectively glued in place with Loctite, okay so far but due for replacement soon.
I won't ever again buy a Cannondale or any other bike fitted with BB30.
Trek's press-fit BB's have just as poor a reputation.
Don't buy a bike with carbon fibre dropouts either. They're mostly only available on high end frames but are prone to compression and abrasion problems.

[Patt0]

The logic of press fit BB in carbon frames is sound. Dont seem to hear of problems with recent bikes which would suggest the manufacturers have learnt their lessons with carbon. Looking at the BB of my two carbon bikes if they were not manufactured exactly right they would be a basket of woes. One is a trek, the other is also Chinese. The trek is appraching 13000km and not a noise or whimper. The other 200km but no problem either.

[MacMan]

One of the reasons I am annoyed for not jumping at the Wilier was that it had a threaded BB. I'm aware that Cannondale are fully committed to their BB30 system and think it's wonderful. Lots of people will tales of woe like yours, Tim.

Good to know PattO that you're having a good run. The problem is that there are just too many people who don't.

So far, it seems that Trek, Giant, Cervello, Merida, Cube, and pretty much everything else I've looked at barring Specialized has some form of press fit. I'm not a buy-and-sell or discard kind of rider, so want something that is going to give a decent lifespan. I hate devices with rubbish bearings.

Happy to hear of any other brands I've missed.

[hamishm]

So far, it seems that Trek, Giant, Cervello, Merida, Cube, and pretty much everything else I've looked at barring Specialized has some form of press fit.

A friend of mine has had no end of trouble with his Specialized Roubaix with press fit BB.

[martin_12]

Happy to hear of any other brands I've missed.

A few months ago I bought a Bianchi Intenso which has a threaded BB. So far all good. I specifically wanted to avoid a press-fit BB. I think some higher level Bianchis have press fit BBs. Some Pinarellos have threaded BBs.

[MacMan]

A friend of mine has had no end of trouble with his Specialized Roubaix with press fit BB.

Interesting - I was looking at the Specialized Tarmac SL4 Sport which is threaded. I mistakenly thought it might have been a brand-wide decision.

[hamishm]

Interesting - I was looking at the Specialized Tarmac SL4 Sport which is threaded. I mistakenly thought it might have been a brand-wide decision.

Maybe they've changed back for 2017. My friend has a Roubaix from a couple of years back. The current Roubaix web pages don't even say what BB format they are using.

[Arbuckle23]

One of my biggest dramas in choosing a new bike. Very keen on the Cannondale Synapse, but a little nervous with the BB30a BB. IS the Shimano press fit much better?

[g-boaf]

So, what are the real-world experiences here with press fit? Are they that bad? If so, how is it that the majority of manufacturers appear to be persevering with them because the frames are easier to manufacture.

General budget is for as little as necessary to get something with >105 components, wheels that won't succumb to having a 198cm 85kg clot on them. Pointers appreciated!

No problems, 4 bikes with this arrangement, all fine. 2 Giants, a Cervelo and a Trek.

[cyclotaur]

There are technical advantages besides cost and mass production, eg. weight and stiffer/more efficient frame designs.

I have 40,000+kms on Cannondale BB30 (admittedly an Alu frame) so far and only one minor problem at about 2,000kms quickly resolved with some maintenance. That was after I rode through some water that submerged the BB the day before... I now also have a carbon Synapse with BB30 with about 3,000kms on it - no problems so far. I think the so-called 'problem ' of press-fit BBs is mostly a matter of preference, and maybe a little attention to maintenance.

I've also had 2 road bikes with threaded BB and the pedal power transfer was definitely not as good as on the BB30 bikes.

But that's just my 2c worth...

[brawlo]

My 2c worth would be to spend the $$ and get a fit done. At your height, there are most likely not many bikes to choose from. I'm saying that as a 196cm tall unit, so you're a tad taller than me. It will come down to your physical dimensions, but you seem to be sniffing around some bikes that didn't even come onto my own personal radar as they were just too small, and if that's the case for you, the fit will definitely pay for itself. FWIW I'm on a 3XL Canyon.

Going to back to your original query on BB, before the Canyon, I had a Felt with BB30 and never had any issues in the few years that I had it before moving onto the Canyon. I was similarly worried about BBs like you are now, but extensive research into creaking seemed to show a lot of the issues were incorrect installation, when the fixes are actually written on the web. I also ride track and I have a love for the threaded BB. After all, where stiffness is king on the track, threaded BBs are still the go to equipment (aside from some very expensive proprietary units)

[chriso_29er]

I have a 4500km old Giant that has begun to creak. Anyone know if this would be considered maintanence or is it a warranty concern?

[Usernoname]

I have a 4500km old Giant that has begun to creak. Anyone know if this would be considered maintanence or is it a warranty concern?

It would only be a warranty claim if the creak if coming from a crack in the frame.

[MacMan]

My 2c worth would be to spend the $$ and get a fit done. At your height, there are most likely not many bikes to choose from. I'm saying that as a 196cm tall unit, so you're a tad taller than me. It will come down to your physical dimensions, but you seem to be sniffing around some bikes that didn't even come onto my own personal radar as they were just too small, and if that's the case for you, the fit will definitely pay for itself. FWIW I'm on a 3XL Canyon.

Very good point. I've used the Competitive Cyclist online tool to get a feel for what size is likely, and it essentially precludes me from the second hand market because suitable bikes appear so infrequently.