Does anyone have an idea how the f*** I can get the screws out without damaging the parts? 

Heating the screws without heating the carbon parts directly. How to do that is another question. Soldering iron??

BSA is my prefered type BB. If nothing else, it is the "devil" I am familiar with. Servicing is super easy too. That said, in the past I've been looking at a frame available with PF30 only and when I expressed my doubts about it this one was suggested as bomb-proof solution:

http://www.praxiscycles.com/conversion-bb/

For other different reason the deal was never closed. That means I can't speak from personal experience. What kind of adaptor/conversion kit did you use if I may ask?

I am not an expert on carbon fibre bike frames. It can be just the image quallity too. However, this is not how I remember broken composite materials to look like (simple fiberglass, kevlar and kevlar/carbon mix of racing kayaks' shells). Without trying to stir any shit, does it not look like there is too much of resin and very little of fibre in that broken seat stay? Or am I completely wrong?

Great video. But wait! Building a bike while not drinking a single beer? Is that even legal?

I am using both kind of brakes regularly. I don't feel any particular need to play an advocate to either of the sides. I would be similarly likely to point out advantages of disk brakes on a traditionalist road bike forum. I have no intention trying to change the minds of people who have already made them up. I simply believe that both sides need to be heard before making a decision. What I wrote above was just a short list of concerns that you can typically hear in the road cycling world that someone not quite familiar with road bikes may want to take in consideration before jumping on the train. I personally  find some of them a bit ridiculous. Sorry if I did not make myself clear enough about that.

That said, I must admit that I am actually one of those who find the look of disk brakes on a road bike to be "wrong". That is of course completely irrational view. I mentioned that one just to show that some arguments against them are rather laughable and I am mentioning it again to show that I may be biased. On the other hand, I got quite comfortable using disc brakes on my commuter hybrid (Spesh Crosstrail) with a no-name Chinese carbon (MTB) fork. If anybody is interested, my commute in the morning includes 700 meters over less than 10 km of a continuous descend. Due to shortage of time I do that on a highway while coming home in the afternoon I enjoy the luxury of a mixture of paved back roads, gravel FSR's and singletrack trails. The point of "knowing how to use"  hydraulic brakes on a long descend is quite obvious. However, sometimes it is not reasonably safe for me to pass those pesky logging trucks whose (strangely sane) drivers insist on not going any faster than 60km/h on that descend and thus I am forced to drag/ride the brakes whether I like it or not. The discs tend to get quite hot in the process (to the point that the spit boils on them instantly). Never had any problems with brakes performance but would not be comfortable pushing them much further (like on a descend twice that long). Those are MTB brakes, even if rather cheap ones (Shimano M446 if I remember correctly), though, and there is/will be a significant push to make the existing/coming dedicated road bike disc brakes as light and generally as small as reasonable possible. The placement of the reasonability line is rather uncertain at this point IMO. Hence the overheating concern.

It is an indisputable fact that the industry is moving towards road disc brakes. What are the incentives for doing that should stay open for another thread if any one is interested to start it. I am certainly not hearing too many demands for them from the road cyclists but maybe I am struck by selective deafness or some other condition middle aged men are prone to. My wife would be happy to give you the full list, I'm sure.  Anyway, the industry will keep coming with new stuff. Whether it is a real improvement only the time can always tell. Btw. our LBS owner just came back from some bike expo and is raving about the new S-Works Allez. For those who are unfamiliar with the Spesh lineup, Allez used to be the cheap, alloy alternatives to the top of the line carbon road racing frames. Well, not anymore. These frames are supposedly  as light as the carbon models now and likely stiffer. Not trying to bash the carbon here, just a response to the remark that road pros used to be against the carbon when it was first introduced.


I personally am unaware of any disc carbon road bike fork failures. That comes with them being untested in the real (road cycling) world. And sorry, cyclocross does not count. Bunch of short steep hills is not a very typical course profile in road cycling. Strangely, and I am actually honestly surprised in this case, not all cyclocross riders are switching to discs either now when they are UCI legal.


Whether one can and will trust the strength of a carbon fibre fork in general and which fork that would be in particular is a question I leave open, too. I am no hater of China-direct carbon and I think it is a great alternative to the hugely overpriced (and similarly China-made) brandname carbon parts. Maybe I am just not an early adopter. Again, everything I wrote here should be taken only as a food for for thought. I am not speaking from any position of authority. If you are ready then by all means go for it. We need the real world testers after all.

Lastly, before I forget, English is not my first language and, chronologically speaking, not my second, third or forth language either. I am greatly thankful for the free English lesson offered as well as any other that may come in the future.

Just a few thoughts, mostly answers to the claims on the advantage of brand carbon parts in comparison to the no-name Chinese carbon.

Unlike metals and alloys, carbon fibre coposites' strength characteristics change depending on orientation of the fibres. Layout of the carbon sheets should be adjusted to the direction of forces that the parts (in this case the bike parts) will be exposed to. Looking at the photos of the broken fork it looks like the fibres simply follow the usual basic crisscross pattern. That is of course hard to say based just on the pictures. What the big name bike manufacturers state is that their designers spend significant amount of time and brain power measuring and/or calculating those forces and applying the ensuing knowledge to the bike design. That well may be true in the top of the line products but allow me to be a little skeptical when speaking about anything other that the WC level stuff. IMO in most cases the layers of the material are more likely simply multiplied in the areas of increased stress.
This can be probably done even without any real engineering expertise simply using common sense, preferably of someone who spends at least some time riding and thinking about bicycles. That is what we should and possibly even can expect from the better of the generic carbon fibre parts made in China. We can also assume that these parts are made in the same factories where the big brands are having their parts made or at least in operations started and run by people who were at some point involved in manufacturing of the brand name products. In other words, they should possess the necessary know-how and skills.
The other issue is the QC. The big brand manufacturers likely do test their products on regular basis as they claim to to assure the manufacturing does not drift too far from the original designer's vision. Frankly, this is unlikely to happen in operations with a limited margin of profit and this will always be and inherent risk in buying inexpensive no-name parts.
However, whoever thinks that his particular fork or frame passed the same stress testing he can see in youtube videos, is badly mistaken. And he better be! Carbon composite materials are all subjects to material fatigue and the tests are intended to expose the products to the use and abuse they can expect over their life time ( as in "life time warranty", i.e. products life time, not yours). I certainly would not like to ride a fork that passed that testing.
Which brings me to the bottom line. Nothing lasts for ever. Neither me nor you nor this whole universe. Not even that newest shiny carbon fibre thingy you've bought for your hard earned cash. Even the big name products fail and sometimes they fail quite spectacularly. Yes, you get what you pay for and no, you can never have all the information you would like to.  There is no reason for bashing the no-name made-in-China stuff as there is no reason to idolize it. Everybody's decisions must be conscious but nobody can know everything. Ultimately, life is a game of chance. One needs to handle his chips wisely but everybody will have only as much fun as he dares to. As long as the laws of thermodynamics are right, at the end the house always wins anyway.

Following is what I (think to) know about Kevlar coming from kayak racing:

Kevlar is lighter and stronger than carbon. Kevlar fibre of a nominal length and diameter is lighter and able to hold more weight than a carbon fibre of the same parameters. However, Kevlar is way more flexible than carbon and kayak hulls built from Kevlar only have unsufficient rigidity assuming the same minimal amount of resin (the less resin, the better, lighter boat) . The result is that kayak hulls are buit with mixture of kevlar and carbon fibres. The ratios vary based on the purpose of the boat. Sprinters need to be super rigid (built mostly of carbon), marathon boats don't need that much rigidity, light weight and resistance to some abuse are desired, hence Kevlar is the material of choice. In the real world it is probably always a mixture of both types of fibres with every manufacturer swearing by its own formula.

How does this translate in bikes and bike wheels I am not too sure. My feeling is that Kevlar would make them too flexible.

That's my $0.02.