The Carbon Conundrum
Carbon fiber. Lighter, quieter, better vibration damping. And potentially quite the spendy habit. There are many places you can put carbon on your bike, from stem spacers to four figure upgrades. While each piece of carbon has its merits, there are certain places where the debate rages especially strong. I’m talking the big money items: wheels and frame.
Here’s a thought experiment. Say you’ve only got enough cash to make one of the two happen – where do you lay down the green on carbon? Let’s assume that the rest of the build is all up to your own personal standard in terms of drivetrain, brakes, seatpost, and so on – and that you’re happy with the frame geometry.
The Chicken or the Egg
Obviously both sides of the discussion have very valid arguments, and neither choice is actually wrong – though the passion with which some approach the topic may have you think otherwise. It’s a bit of a chicken-or-the-egg scenario. Weight, stiffness, ride quality, durability; you can argue either way for any of these.
The damping argument goes for both rims and frames. Weight savings are more discernible in the wheels, hands down. Wheels are, however, easier to upgrade later on – but by the same token can be easily swapped between bikes. A carbon frame has a distinct ride quality, yet so do carbon rims. Carbon rims track straighter and don’t flex as much for a given weight, but the same can be said for carbon frames. Carbon rims don’t bend or dent – but they do crack. When it comes to longevity, the two are again comparable. How many of us own frames that have been upgraded time and time again, or have wheelsets that migrate from bike to bike?
In general, both of these upgrades will cost you about $1500 at retail – but which gives you the best bang for the buck? In my experience, people balk at the price of carbon rims much more often than the price of carbon frames. Is this because, percentage-wise, carbon rims can be 5x the cost of aluminum while a frame might only be 1.5x more expensive?
(I would also contend that more people have ridden a carbon frame than carbon wheels; you can’t really walk into a bike shop and buy an aluminum bike with carbon rims.)
Door Number Three
There is, of course, the unmentioned third option of spending the money in another place altogether. With that much money you could pack up your bike and take off to Moab for a week to put a true experience under your wheels.
So therein lies the question… where do you spend your $1500?
Comments
Russ Wortman
10 years ago
The best part of this article is the the "door number three" paragraph. Buy what you can afford and go to Moab. Best advise anyone will ever give you.
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XC_chicken
10 years ago
I switched from AL to CF this year. Same frame, same geometry as the AL version. Was a warranty deal. AL frame cracked. Known issue. I asked to pay the difference for the CF frame. I wasn't sure if I made the right decision. It was an extra $1000. CF frame was only 185g lighter and apparently 11% more stiff. I can't say I felt the CF frame cut any vibration as it's a dual squish bike and the suspension I suspect would play the more significant roll in vibration dampening.
I was surprised that there was a noticeable difference in steering response and front end stability. The AL frame seemed quite good to me, didn't have any complaints, but the CF frame is better. Is it $1000.00 better?
Probably not, but I'm not upset with my purchase so far. I would have got a better performance improvement from CF wheels instead… But… Will get CF wheels anyway (probably China or Taiwan rims, and I'll build the wheels myself) so I'll have both.
I'm convinced CF is the way to go technologically, but price wise the value to usefulness ratio still has some room for improvement.CF upgrade was gift to myself and not really needed. Got lucky, had some extra cash this year 🙂
I like CF bars and seat post. Weight can be cut in half and durability is proven. So long as it's made right it shouldn't be an issue. I'm sure formula one cars deal with a lot more stress than a bicycle, ditto for jets and spacecraft- each using CF successfully. Don't know if we get that tech in bikes, but it definitely shows CF is well established and beyond the proof of concept stage as a material. Anything is possible though.. Someone could develop a new alloy and we'd all be pining for that..
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rob c
10 years ago
I work in bike industry (retail) in the workshop environment and do a lot of warranty / crash replacement - mainly for customers with carbon fibre road bikes and less for mountain bikes
today I had 3 road bikes come into my workshop, all carbon, all with "issues" (i.e. cracks) relating to the frame or forks, 2 were not warranty related (both crashed), the other 1 was a valid warranty despite being 8 years old and ridden very hard.
I've dealt with 100's of warranties and crash replacements on aluminium and carbon bikes for some years; the genuine warranty jobs tend to be manufacturing (QC) issues or structural (design flaw) issues. You will see the same issues time and time again on the same model of frame and it becomes well known among people dealing with these claims.
A common design issue causing repeated warranty claims on some specific models was galvanic corrosion between aluminium alloy hardpoints (BB shell, head tube cups) embedded in the carbon structure.
Personally I ride a carbon road bike, and carbon fibre hardtail mountain bike.
My CF mountain bike was a warranty replacement for an aluminium alloy hardtail that had a manufacturing defect, they upgraded me to CF as a goodwill gesture. Since then, I have had another warranty replacement of the same carbon fibre frame due to an "known" structural issue with my current frame.
The manufacturer has stood behind their product 100% and their 2014 frame has been redesigned, I know once my current frame develops the known issue I will be moved onto the new model. I have no qualms riding carbon fibre frames.
If I had spare cash? I would definitely ride carbon wheels on my mountain bike, but probably not on my road bike as I do a lot of commuting miles in bad weather (350km / week) and prefer "hand built" wheels with common Mavic Open Pro alloy rims.
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t.odd
10 years ago
if I had a spare 1500, I certainly wouldn't be wasting it on wheels for a pedal bike.
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Jerryek
10 years ago
That's a tough call. I have a cf frame and wheel set. Both are much better than aluminum. But I'd have to say the wheels. Such a huge difference in terms of speed and stiffness.
And everyone who is complaining about durability: cf rims are more durable! Period! Unless you're riding rims outside their intended purpose, they should last a long time. The new hookless setups are even more durable, as they eliminate the one major problem with older designs.
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Jonathan Harris
10 years ago
I have to say that I'm a big fan of bike trips. They always get my stoke factor maxed out. If I had $1500 spare I would definitely throw it at getting up to the Yukon to ride again, in fact I think you can do a four or five day trip there for $1000 even if you fly up. That leaves $500 for some tasty carbon cranks.
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Cr4w
10 years ago
I don't really fully trust carbon rims enough at this point to risk $1500 on them given my habit of brutalizing rims. I'm watching the development happening and will likely buy some eventually - I want to see what happens with this new crop of super-wide rims.
I had a carbon Enduro and now I'm on an alloy one; I can honestly say I that I'm perfectly happy with the ride of alloy and with $1500 in my pocket to spend on road trips plus whatever else. Plus with the alloy frame I can ride it with complete abandon and put it away wet. I can get a complete new Enduro Comp for less than the price of an Enduro carbon frame.
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Jonathan Harris
10 years ago
After seeing a video of a new ibis rim being tested I think that the longevity question on carbon rims will go away, especially with the new hookless designs. Mine have lasted a whole season without needing to be trued and taking some direct hits over rocky sections to the rim itself without denting.
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Vik Approved
10 years ago
I got 2 Light Bicycle carbon rims delivered to my door in Canada for $400.
They look great and so far have worked great.
You don't need to spend thousands to get carbon rims.
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Cr4w
10 years ago
Absolutely agree. You can get wide Derbys for around $300/rim which is totally reasonable.
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Rivers Mitchell
10 years ago
Agree…I just did the same thing and so far love them. Then I saw the new Enve rims and almost pooped when I saw the $999 per rim price…just wow. Not worth it at that price, but $400 shipped to my door…that is a price I can swallow for an upgrade like this.
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Vik Approved
10 years ago
Buy the best suspension and wheels you can afford [best not meaning most expensive, but best suited to your needs] and then if there us $$ left over go on a road trip.
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John Rodriguez
10 years ago
I'd definitely rather spend it on a trip. I just don't see either letting me a) ride faster or b) ride longer/farther w/less fatigue.
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Mihr Cycles
10 years ago
I am learning to trust carbon on my AM bike… wheels and frame. I say go for it.
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Garrett Thibault
10 years ago
I have a habit of destroying rims. Bit of a risky place to put $1500 for me.
That being said, I have had an alu wheelset outlast an alu frame.
Conclusion: save the money.
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kain0m
10 years ago
Never, ever. Carbon fiber is a great material, but as we've seen in many, many instances, it isn't perfect. Aluminium parts bend - carbon parts rip apart. I've ridden a dented Mavic EX729 rim for a few seasons, never any issue. Same impact would've ruined a CF rim. Same for frames - huge difference between a dent Al frame and a wrecked CF option.
I'd rather spend those 3-4000$ you can save by going Al instead of CF on a few nice (bike) vacations and/or other parts/clothing/beer.
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Jerryek
10 years ago
The idea that cf fails more than alu is a myth. It's science.
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Vik Approved
10 years ago
I'd agree that CF is exploding all over the place. The science is that CF structures are stiff and strong, but also brittle compared to metal. So they can make light/stiff frames and they can withstand some serious impacts "if" the impacts are not so concentrated that it cracks the carbon layers.
Crashing on a sharp rock would dent a metal frame and crack a CF frame.
You can protect vulnerable areas on a CF frame fairly easily with products like Shelter Tape. CF frames can also be repaired more easily than metal frames.
So it comes down to what matters to you most and how you evaluate the risks.
I just bought a bike with a CF frame/bars/cranks and rims. My old bike which I still ride has no CF.
I don't think there is a clear winner. They both have really good points and both have some drawbacks.
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kain0m
10 years ago
Honestly? I am 100% certain CF is LESS durable as a mtb wheel material than Al. It all boils down to "failure". What is failure? I wouldn't count a dent in a rim as a failure. I will, however, count a cracked rim as a failure. (Of course, the carbon doesn't bend (as in permanent beding), so you won't need to re-true such rims over time as much.)
With mountain biking, we put enormous stress levels on our equipment, especially rims. What kills them are the short load peaks. These will warp an aluminium rim, and crack a carbon one. These forces can't be predicted accurately, and so the rim has to be designed with two aspects in mind:
-durability in the long term
-ultimate strength
Long-term durability kills Al rims, it isn't an issue with CF. For ultimate strength, the opposite is true. What this means is that you can build a very light CF wheelset, which will last forver. But stress it too far even once, and it will break instantly. And for rims, a crack is a 100% certain death sentence. Frames can be repaired in theory, but it's still going to be costly and increase the weight of the frame. With an Al rim, there will be a dent - no big deal, you keep on riding it.
Conclusion: CF is a great material. It is hugely strong, relatively light, and can be very durable. But as any material, it isn't perfect for every application.
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Henry Chinaski
10 years ago
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Mihr Cycles
10 years ago
Nah, carbon can be stronger than alloy… that's unpossible… 😉
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kain0m
10 years ago
This is of course such a valid test… unknown carbon rim, unkown Al rim. And the "test" consist of nonsensically bashing them into the ground. Surprised they didn't shoot at them with a gun, would be just as good a test…
Just for giggles: Al can also take a beating. Cheapo Rim, by the way:
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Vik Approved
10 years ago
The real test is the hundreds and thousands of carbon rims that are being put on MTBs and ridden on trails. If there are major problems they be reported online just like any other MTB failure and if not in a year or two folks will be forced to acknowledge they are holding up fine.
Personally I don't care what happens. I'm trying some carbon rims out and if they last a long time awesome. If they don't I'll go back to AL.
Before buying my carbon rims I checked with a number of early adopters of carbon that I know and I got lots of positive feedback and heard very few problems from real world riders.
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Matt Dennison
10 years ago
I'd spend it on new riding gloves. Which I'd leave home anyway because gloves aren't cool.
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