Will I regret getting a carbon frame?

The Defy sounds like the go to me, they're great bikes. how big is the discount? Is it possible to test ride both?

I've already test rode both; I do like the Defy the best... I'm just worried about the longevity of the carbon frame.

Why are you worried about the longevity of a carbon frame? Did someone plant a seed in your head that they don't last? A hard crash can destroy a frame made of any material. True, titanium is pretty robust as are the old thick walled steel frames but other than that any frame could be trashed with one accident and many frames can potentially live through a few accidents. And remember not all carbon is created equal, the lighter stiffer high modulus carbon is not great in accidents which is why many manufactures combine different types of carbon for a combination of weight, stiffness, and strength. Cannondale in fact says their SuperSix Evo is more crash resistant than their aluminum CAAD9, which is pretty darn crash resistant. The only material that cannot really be trusted after getting bashed up is aluminum, and it's the only frame material that cannot really be fixed reliably or cost effectively.

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This 6 year old is holding up a 13lb steel bike that would probably crumple faster than any CF bike in an accident. If you do however have an accident, and it's not covered under warranty CF can often be reliably repaired by one of the dozens of reputable carbon smiths around the country and world. Example: http://brooklyncarbon.com/

But you are getting a new bike with a warranty, right?

Quoted post said:

Originally Posted by Nevy
I've already test rode both; I do like the Defy the best... I'm just worried about the longevity of the carbon frame.

You might be right to worry about longevity. Not because the Defy frame/fork is CF, but because it's a lightweight road bike designed for smooth paved roads. Road bikes aren't designed for "really bad gravel roads", "bumpy roads" ,"mild dirt trails" or "awful farm/service roads". The frame and fork take a real beating riding over rough stuff on 23 mm tires, and this pounding does reduce the life. The fork could be subject to overload failure, ie, you hit a big bump or pothole that exceeds the design limits of the road fork, and it breaks.

Note, I trust CF forks. I'm riding a 10 year old Ouzo Pro fork with 35K miles on it, and don't worry about it's safety. But those miles have been on smooth roads, with just a small number of potholes and big bumps.

If you really want a bike to hold up for many years of this kind of riding, I think you should consider another cyclocross bike, or even a hybrid with a front suspension. Suggest you discuss your needs with a good LBS. Get the equipment designed for your intended usage and you'll be happier in the long run.

Yeah, I understand what you're saying. The thing is that 85% of my riding is on smooth, flat roads, but there are times when getting from A to B I have to muck through some gravel, maybe I'm feeling a bit adventurous and want to check out a path leading into the woods, or whatever. Even if I owned two bikes I'd want to take the road bike almost every time I go riding, and still wind up riding on some bad roads at some point.

Bad roads are inevitable. At least in the US. I would think if the vast majority of your ride time is spent on smooth pavement, any quality bike should be able to handle a rough patch now and then. Common sense, though - just don't push your luck. If it's too rough, avoid it or walk the bike.

I'd second what both guys above said. Also, 23c tires are so 90's, what about switching to 25's? It's hard to believe but they actually do make a very slight difference with absorbing road shock. I've pretty much migrated permanently, and a lot of fellas race on them myself included, even the lighter ones. Not running at max tire pressures helps too, especially if yer not a big fella but careful not to run the pressure too low over choppy stuff as you may be more likely to get a "pinch flat" than a bona fide puncture.

How does that old saying go? Discretion is the better part of valor, and it may apply to that inviting path off the beaten path. I ride on some pretty bad roads and will not avoid a dirt road on my CF road bike, I will however seek to avoid the craters and if a dry river bed pops up, I'll probably walk the bike across ;P

Quoted post said:

Originally Posted by Nevy

Yeah, I understand what you're saying. The thing is that 85% of my riding is on smooth, flat roads, but there are times when getting from A to B I have to muck through some gravel, maybe I'm feeling a bit adventurous and want to check out a path leading into the woods, or whatever. Even if I owned two bikes I'd want to take the road bike almost every time I go riding, and still wind up riding on some bad roads at some point.

Nevy, check out the Cannondale owner's manual, from page 51 on, about "intended use" categories and how to select the right bike.
media.cannondale.com2010 Cannondale Bicycle Owners Manual 124451.pdfOpen ↗

As if states, their Category 1 Road bikes are made for paved road riding only. With 15% of your riding off paved roads, you're probably at a Cat 2 or 3. At some point, it depends how much you are willing to compromise life of the frame and fork to get lightweight. Note the warranty doesn't cover fatigue and impact damage to the frame (see some example photos). You might get a replacement frame or fork on "customer goodwill", but to me buying a bike that's not strong enough to hold up to your use profile is just not a good idea.

I particularly like the advice that the buyer should consult honestly with the LBS about what they want to do with the bike so they get the right equipment. Picking out the fastest-looking bike, or the one that's on sale, is tempting to all of us. But if it's not what you need, it's a bad choice.

The following section in Part II explaining how metal and CF frames fatigue and how to inspect them are well worth reading too.

PS: A couple of months ago, I went on a gravel rails-to-trails ride. One of the guys I went told me I could probably get away with my road bike, but he offered me his spare mtb. After doing the ride on that bumpy gravel trail, there is no way I'd want to beat up my road bike on it. The 23 mm tires on the road bike would have made it hard to pedal and stay upright, and the constant bumps on some sections would be brutal on the wheels, frame and fork. The hard-tail mtb with suspension fork and wide tires was a much better choice.

Quoted post said:

Originally Posted by dhk2

media.cannondale.com2010 Cannondale Bicycle Owners Manual 124451.pdfOpen ↗

As if states, their Category 1 Road bikes are made for paved road riding only. With 15% of your riding off paved roads, you're probably at a Cat 2 or 3. At some point, it depends how much you are willing to compromise life of the frame and fork to get lightweight. Note the warranty doesn't cover fatigue and impact damage to the frame (see some example photos). You might get a replacement frame or fork on "customer goodwill", but to me buying a bike that's not strong enough to hold up to your use profile is just not a good idea.

dhk2, it is wise advice asking the rider to take an accurate inventory of the type of riding they will do and match it up with an appropriate bike.

One thing it's also important to consider however is that the Cannondale manual is written from a minimum liability standpoint, carefully vetted by lawyers, both to maximize a riders safety as well as Cannondale's liability.

I see the max rider weight on these bikes of 275lbs, and it should be noted that a rider of 275lbs will deliver significantly more stress to a frame under any riding conditions than say a rider of 175lbs. A rider of any weight will deliver more stress to a frame with 23c pumped to max inflation vs. 25c, or 28c tires at a lower pressure. And even then wheels may suffer the major brunt of damage before the frame does.

The truth is many of these Tier 1 bikes are raced over some of the toughest roads (often cobble stoned) in Europe, and although they could be replaced after each event, many riders will use the same bike all season. Safety is a big consideration, but as far as longevity, we also have to ask ourselves do we want our bikes to last indefinitely, 10 years, or are we ok with riding a bike hard with the understanding we may have to replace it in 5 or 6 years (or even sooner)? Are we willing to make a tire change the night before a rough coursed event to compensate for adverse road conditions, and do we possess (and are we willing to engage) the riding skill to avoid high impact obstacles most likely to damage the bike? Some riders are fine (or only comfortable) with riding a straight line and hitting whatever they may come across.

I am not making these points to be contentious, but they are important factors to consider regarding a bike's longevity that the lawyers at Cannondale would never allow to enter any manual for public consumption. It's simply food for thought.

Yup, we legal professionals are a serious bummer ;-). But true, what a manufacturer tells you can do with equipment and what you can actually do can be very different. Again, common sense. Personally, the ideal solution would be different bikes for different rides. Not everyone can or wants to do that. I view it like fishing - it takes very different rods, reels, and tackle to go fly fishing than ice fishing or trolling for salmon on the open waters of Lake Michigan.

Quoted post said:

Originally Posted by MotownBikeBoy

Yup, we legal professionals are a serious bummer ;-)

I can neither confirm nor deny that one or two of your colleagues may have gotten me out of serious trouble, once or twice. As I like to say, there are two things one should never skimp on: legal representation, and plastic surgery 😉

Quoted post said:

Originally Posted by dhk2

You might be right to worry about longevity. Not because the Defy frame/fork is CF, but because it's a lightweight road bike designed for smooth paved roads. Road bikes aren't designed for "really bad gravel roads", "bumpy roads" ,"mild dirt trails" or "awful farm/service roads". The frame and fork take a real beating riding over rough stuff on 23 mm tires, and this pounding does reduce the life. The fork could be subject to overload failure, ie, you hit a big bump or pothole that exceeds the design limits of the road fork, and it breaks.

If that were the case you wouldn't be seeing the plethora of carbon framed mountain bikes, cyclocross bikes, and road bikes that perform well in Paris-Roubaix (with carbon rims) every year. Carbon can take a beating, but it is vulnerable to impact and crushing loads like that from flying rocks, roadside boulders, curbs, and overtightened seat post and stem clamp bolts.

The main reasons for not using a carbon bike on dirt and gravel are that some of the more "race oriented" geometries are just uncomfortable and unpleasant to handle on anything but pavement, and tight clearances prevent the use of fatter tires.

These days any carbon frame by a major brand that comes with a warranty against manufacturing defects is as safe a bet as any.

Quoted post said:

Originally Posted by Nevy

Will I regret getting a carbon frame?

No. Don't believe all of the second and third hand horror stories you heard about online. Carbon's been around for awhile, and Giant makes great frames. So good that other companies---including Trek---outsource their frame designs for Giant to manufacture. If you buy a Trek Madone series 3, 4, or 5, or any Domane, you're probably buying a frame that Giant made for Trek.

The Giant Defy carbon is suitable for the odd run on crappy roads. Remember that the Defy was designed to handle the pave on the Paris/Roubaix and other spring classics. Gravel and crappy road surface in places is nothing in comparison to that!

We have some major sections of crack and pothole filled roads, chipseal and gravel. I know 3 or 4 guys riding Defys and none have had an issue with frames or forks (other than paint chips).

I've ridden on them all on a carbon framed bike (an old 2001 Trek 5500 9 speed) which has never had a problem handling them. I agree that if you ride them a lot you might consider 25mm or even 28mm tires. I have 28s on my cross/commuter and they handle the rough stuff better and I run lower pressures (max 90 psi) than on a smooth road. Make sure you have some bombproof wheels and leave the Lightweight Obermayer Golds at home!

Good discussion here. Didn't mean to say that the Defy isn't capable of handling "the odd run on crappy roads". But for those planning to use the bike both on and off pavement regularly, Giant does make and recommend a separate range, their X-bikes. And to me, the 15% of gravel roads and trails that Nevy describes is a significant usage.

Agree rider weight is a key point. As a heavier (210 lb) guy, I'm putting a lot more load on the frame/fork over bumps than lightweight rider. And tires are a key point too. My road bike won't handle anything bigger than a 25 mm tire due to the limited rear stay clearance. For any kind of off-road such as gravel rails-to-trails, I like a wider tire. I've ridden on well-groomed and dry crushed limestone trails with my 23mm tires, but I think wider tires are faster and easier to handle on those trails.

From my perspective, for on and off-road use, it's better to err on the side of utility, strength and durability by picking a real cross style bike. You gain the ability to fit wider wheels and tires, plus a heavier frame and fork which should be more capable of taking a beating for years and years. The penalty on the road vs a real road bike seems worth it to me. But I value durability in frames/forks/wheels over saving a few pounds. Sadly, I'm carrying enough extra now that I don't need to worry about adding a few more to the equipment under me, and no longer have any aspirations to race......YMMV of course.

Ohio is the nation's poster child for really crappy roads. One of my carbon frames has survived approximately 25,000 miles with no problems. A second, different brand. carbon frame cracked after less than a year of service. Both were ridden only by me and 99.99% of those miles was on paved (kinda sorta...it IS Ohio!) roads.

Sometimes it just comes down to chance...and having a good warranty that's backed by a reputable seller.

Quote by mpre53:
"Carbon's been around for awhile..."

A friend bought the first Kestrel in our area, way back in the dark ages...1986. I'm guessing here, but I think he put over ten years on it before retiring it (it finally developed a crack). It held up very well.

I like carbon bikes and would prefer it over my steel and titanium bikes for every type of road riding I do. That said, there's still plenty of room for better quality control and safer designs on the market (read: heavier models that use more material).

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Thanks for all the discussion guys.

I should point out that I was already planning to put 25 or 28's (if they clear) on the bike, and that I'm a pretty light rider (130lbs) And I definitely wouldn't be using nonsense racing wheels for my everyday riding.

Jimbo pretty much said what I had been thinking to myself: "If this bike is made to ride Paris Roubaix it should be fine on my roads"

I'm thinking that I will be getting this bike because I am REALLY pleased with it and the clearance discount is great.

+1 campybob About bikes using more material. The way I feel when I go looking for a bike is that there is a big middle ground that I'm looking for which just isn't filled for some reason.