Tuesday, February 8, 2011

Is Carbon Fiber the answer?

And if so, what are the questions?

I have been a bit of a CF (carbon fiber) skeptic, based mostly on past performance and some recent performance of one brand of bike in particular.  But a recent conversation with a bike company owner that is making inroads into CF frames and components was interesting in the absolute statements in the discussion.  He said that a well built CF frame will last waaaay past the life span of an alu frame of the same type.  Not just as good or maybe as good, but speaking to failure related to fatigue cycles...and that is the typical killer of alu frames...CF was so far beyond that as to be impossible to break due to just pedaling it to death.  Basically, the thought here is that it is beyond the ability of a human powered motor to ride it long enough and hard enough to get beyond the fatigue failure point.  Then we looked at a new CF handlebar they have coming to market and he said basically that the CF bar was so much stronger than the alu version that it was just off the charts....lighter, too.

Now taking crash damage out of the equation, that is a pretty strong statement and came as a response to my musing that I like a metal frame because I tend to keep my bikes a long time.  The reply was, in that case, that CF is the material of choice for guys like me too and not just a one season, race day frame.

Now, like any material that bike frames are made from, the devil is in the details.  Just because it is glue and cloth stuck together does not make it Kryptonite.  His comment was assuming a well engineered and well built frame that did not try to be the lightest and/or cheapest thing out there on the market.  If there is any one of the materials that require intense QC, it is CF.  They all look good on the outside, but the insides are where it all comes together.  The way the bladder works to keep wall thickness and shape correct, the quality and alignment/layering of the cloth, the heat applied, etc. And I am a complete novice and may have not gotten even the terms right, but just about anyone can pick up a dozen sticks of steel and get a reliable steel frame.  Even alu is easy.  Just keep it to thick pieces of tubes, stick it in an oven, and it will do fine, pretty much.  Ti is a bit trickier.

So there really seems to be a minimum standard here.  Remember the old adage:  "Light, Cheap, Strong...pick two."?  That really seems to apply to CF over any other material.  It sure can be light.  I am riding a CF Breezer 29er HT in an XL size and the frame weight is purported to be 2.5lbs.  Wow!  It also pedals like nothing else I have ridden that was not CF.  According to the previously mentioned bike company owner (and others), it sure can be strong, if they are to be believed.  I was talking to a buddy that works for Ibis Cycles and I asked him how CF has been for them as far as warranty or failure on the well liked Mojo and Tranny bikes.  He just flat out said it is not an issue and they rarely see a failure, even under very hard riding conditions.  Sure, stuff breaks, but they have no more and likely fewer issues than if they were making alu versions.  Their frames are not cheap, but they are lasting and lasting.

Another thing I hear from product mangers is how CF will never get that much cheaper due to the high level of labor and time involved in making it.  It is easy to pop out thousands of expanded 'beer can' alu frames one right after another and robot weld them in fixtures.  CF is hand made for the most part.  And, since I want my CF to last and NOT break, I am sure looking for a builder who had someone perform the due diligence of proper engineering and QC all along the creative process.  I also assume that all that QC attention takes time and money. That leads me back to the adage of "...pick two".

Most of the CF is coming out of China.   And now, direct to the consumer from the manufacturer, are CF frames that are are light and cheap...really cheap.  Some of that cheap is from eliminating the middle man...I get that, but ya gotta wonder who is looking out for the end user here?  Ibis is looking out for the Ibis bike buyer.  Niner is looking out for the Niner bike buyer...Specialized, Giant, Breezer, etc.  Who is looking out for you from the China-Direct factory?  Will they answer the phone, and if so, what would you say?  Can you talk to the product manger?  Scary?  Maybe so.  Time will tell.

However, if the cheapy CF frames do hit all three of the points in that adage, then watch the big dog's prices fall on CF frames.  They will have to just to keep the informed enthusiast on board.

But, I digress.  I still love my steel SS.  It is not costly, it is smooth riding, fun, and will last for years.  But this new CF frame I am on is impressive.  It rides very well, not quite like the steely, but not harsh at all.  It is at LEAST 2 lbs lighter.  That is a lot.  It pedals like nothing in steel can do, IMO.  Crazy responsive and just rock solid at the BB.  It has shapes that can be tweaked to get just what the designer wants in the way of performance.  And, as long as I do not punch a rock through a tube or chain suck it to death, it may outlive me.  I bet it will outlast the alu HT frame I have 10-1 based on the amount of flex in the alu frame I see and it is probably lighter still.  Flex kills alu.

Crazy.  And hard to ignore.  I already would prefer a good CF h-bar.  I trust them.  I sure see the bennies of a CF frame (I can't imagine racing anything else but CF) and a may yet come to trust them.

So, I still have questions.  But more and more, CF is providing the answers.

1 comment:

Anonymous said...

I used to work in R and D in F1 car racing ,, and as you can imagine we used to sample and test every component,, with constant QC with every manufactoring step, yet we still had failures,
we were building to very small safty margins but many failures were from the human element of the construction,,
as you said the problem with CF is it can look great from the outside , and a lot of effort with bike companies is in the BS factor of the outside layer ,, but inside it is a very differnt matter,,
and often crash damage doesnt even show on the outside,,

the failure mode of carbon ie sudden catastorphic failures rather than the more gentle crack and bend of a metal frame is a cause of concern ,, the internet seems to have a quantity of pics of failed CF bikes and components .

having said that i have carbon forks on two of my bikes,,