You can’t help, but notice a lot of the new mountain bike designs are featuring carbon frames. The Luddite in me says carbon is too fragile and too expensive to be a good choice. However, when you look at companies like Santa Cruz and Ibis that have gone heavily carbon you don’t see huge amounts of failures being reported in the online forums. Additionally these are both smaller boutique brands that rely on their reputations to justify higher sticker prices compared to the major players like Specialized. If Ibis suddenly had a reputation for frames breaking they’d go under in a heartbeat.
I found this interesting discussion of different frame materials linked on the Ibis site. It was written a few years back before the current generation of Ibis frames were designed and it is worth a read if your keen on understanding the differences in frame materials.
Talking to a couple Santa Cruz dealers they were both super stoked about the carbon frames and felt they were superior to the aluminum in almost every way. They even went so far as to say the carbon frames were as tough or tougher than the metal frames. You could just chalk this up to salesmanship, but these are some longstanding well respected bike shops that rely heavily on customer loyalty and reputation to sell high end bikes.
Going carbon for a Santa Cruz Blur LT costs$564USD and saves you a pound for a similar build in aluminum. The frame will also be stiffer and can be made in shapes not possible for a metal bike. In the world of high end mountain bikes $600 to save a pound and get better ride quality is well within the spectrum of what’s considered acceptable.
So after a bit of poking around the choice of carbon fiber for a mountain bike frame material doesn’t seem as crazy as it did when I started thinking about it. Ultimately the proof will be in the pudding. With so many carbon frames out in the dirt it won’t be hard to get a feel for how they are holding up by seeing what riders are posting online.
As a side note my buddy Kurt had a Cannondale Raven which was one of the first carbon fiber mountain bike frames made. He abused it pretty well until the frame failed. Interestingly the part that failed was the aluminum insert at the headset not the carbon fiber. He rec’d a Scalpel as a replacement since Ravens were out of production at that point. The Scalpel uses carbon fiber chainstays without a pivot so they flex as the rear suspension compresses. He’s been riding that frame hard for years and it’s still going strong.
BTW – if you want a deal on some aluminum Santa Cruz bikes aluminum Blur LTs are being sold off online by riders upgrading to the carbon Blur LT…same thing is bound to happen when the carbon Nomad hits the trails this spring…you’ll be able to snap up some used aluminum bikes at great prices.