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  1. #1
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    I need advice, Carbon or Aluminum?

    So, as I enter my 3rd year of riding, I have finally learned that biting the bullet up front and buying the bike you really want is more prudent than going for the smaller sticker up front and upgrading as you go.

    As a result of this epiphany, I find myself faced with a new dilemma: I have decided to build a trail bike from scratch, so should I opt for a carbon or aluminum frame?

    It's a 6" travel frame.

    Factoring in the weight savings, the increased stiffness, and the better dampening of carbon, it seems to be the clear winner in every category save one: impact resistance. I'm actually pretty concerned about this since I seem to crash more frequently than most of the people I ride with.

    Should I stay with aluminum?

  2. #2
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    Quote Originally Posted by El Castigador
    So, as I enter my 3rd year of riding, I have finally learned that biting the bullet up front and buying the bike you really want is more prudent than going for the smaller sticker up front and upgrading as you go.

    As a result of this epiphany, I find myself faced with a new dilemma: I have decided to build a trail bike from scratch, so should I opt for a carbon or aluminum frame?

    It's a 6" travel frame.

    Factoring in the weight savings, the increased stiffness, and the better dampening of carbon, it seems to be the clear winner in every category save one: impact resistance. I'm actually pretty concerned about this since I seem to crash more frequently than most of the people I ride with.

    Should I stay with aluminum?
    Carbon is fine. I've been on my plastic bike to 1.5 years, have tossed it down a rock face at Whistler, have had countless rocks fly up and hit the downtube and it is in perfect shape. I have total faith in a carbon frame. Everything eventually breaks. If an impact is big enough to break a carbon frame, it will most likely destroy an aluminum one too.

    The dampening of carbon is pretty nice too. Makes my bike feel solid to me.

  3. #3
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    Quote Originally Posted by El Castigador
    So, as I enter my 3rd year of riding, I have finally learned that biting the bullet up front and buying the bike you really want is more prudent than going for the smaller sticker up front and upgrading as you go.

    As a result of this epiphany, I find myself faced with a new dilemma: I have decided to build a trail bike from scratch, so should I opt for a carbon or aluminum frame?

    It's a 6" travel frame.

    Factoring in the weight savings, the increased stiffness, and the better dampening of carbon, it seems to be the clear winner in every category save one: impact resistance. I'm actually pretty concerned about this since I seem to crash more frequently than most of the people I ride with.

    Should I stay with aluminum?
    Stay with aluminum.

    How many aluminum bikes do you have to cover with "frameskin" to avoid chips and cracks?

    The ding resistance of carbon relegates it to XC only.
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  4. #4
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    Quote Originally Posted by iheartbicycles
    Stay with aluminum.

    How many aluminum bikes do you have to cover with "frameskin" to avoid chips and cracks?

    The ding resistance of carbon relegates it to XC only.
    I agree. I personally don't see the reason for a 6" carbon fiber bike, but that's just me. OK, less flexy. It's a 6" bike. It's only going to pedal so well. It costs a hell of a lot more than aluminum and then there's the impact resistance issue.

    I got doored on a night ride and rode away with a large-ish dent in the downtube. I bet I would be calling a cab and throwing my two-piece carbon fiber frame in the trunk had it not been aluminum.

    Even if it's just as strong, something tells me carbon will fail in a bigger, badder and more dramatic way. Then again, MichiganMat's entire headtube/handlebars flew off at Boggs. It was aluminum -- even if a cheapie off-brand...

  5. #5
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    Quote Originally Posted by iheartbicycles
    Stay with aluminum.

    How many aluminum bikes do you have to cover with "frameskin" to avoid chips and cracks?

    The ding resistance of carbon relegates it to XC only.
    there are many who would disagree....
    carbon is used extensively in; professional race cars, military applications, nasa and other applications where rigorous stress and impact resistance is required

    imo, its simply a matter of personal preference.
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  6. #6
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    I could try to reach into the depths of my memory to my engineering days and come up with a well-reasoned answer backed up with solid facts and logic. But that would be hard. So I won't.

    Instead I'll go with the "get the one you want" answer propounded by racerick. If you'll always be stressin' about crackin' a carbon frame while you ride, that would suck. Get aluminum if that's the case. If you'll be pining for the low weight, stiffness and damping of carbon and have regrets every time you throw a leg over an aluminum steed, that would suck. So get carbon if that's the case.

    Either way, right now you should have a beer. Then another.
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  7. #7
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    Quote Originally Posted by jdubsl2
    I agree. I personally don't see the reason for a 6" carbon fiber bike, but that's just me. OK, less flexy. It's a 6" bike. It's only going to pedal so well. It costs a hell of a lot more than aluminum and then there's the impact resistance issue.

    I got doored on a night ride and rode away with a large-ish dent in the downtube. I bet I would be calling a cab and throwing my two-piece carbon fiber frame in the trunk had it not been aluminum.

    Even if it's just as strong, something tells me carbon will fail in a bigger, badder and more dramatic way. Then again, MichiganMat's entire headtube/handlebars flew off at Boggs. It was aluminum -- even if a cheapie off-brand...
    I've owned 1/2 a dozen carbon MTB's and all of them took a beating and it showed.

    people are going to have a hard time convincing me otherwise, since I've owned so many different carbon bikes, and without fail, they show dings, chips and stress fractures much more readily than aluminum.

    Remember that el castigator is looking for a new 6" travel bike, and that he crashes lots.
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  8. #8
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    Quote Originally Posted by jdubsl2
    I agree. I personally don't see the reason for a 6" carbon fiber bike, but that's just me. OK, less flexy. It's a 6" bike. It's only going to pedal so well. It costs a hell of a lot more than aluminum and then there's the impact resistance issue.

    I got doored on a night ride and rode away with a large-ish dent in the downtube. I bet I would be calling a cab and throwing my two-piece carbon fiber frame in the trunk had it not been aluminum.

    Even if it's just as strong, something tells me carbon will fail in a bigger, badder and more dramatic way. Then again, MichiganMat's entire headtube/handlebars flew off at Boggs. It was aluminum -- even if a cheapie off-brand...
    How many aluminum frames have you broken?
    Remember walking 2 miles at Saratoga Gap when your aluminum Stumpy failed?

    In the end everything will fail given the right circumstances, everything.

    Get what you want, it's all personal preference. I was a carbon hater until I got one, and I absolutely love it. My carbon frame fear is over.
    If carbon was truly an inferior material I don't think Santa Cruz, Trek, and Specialized (three of the biggest bike manufacturers) would be building 6" travel bikes out of it. That being said, I will never run a carbon seatpost or handlebar on a MTB. It's just in my head to think that they are inferior and will fail in a major way.

    I wonder how many people that say never get a carbon frame are running carbon seatposts or handlebars.

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  10. #10
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    Quote Originally Posted by racerick
    there are many who would disagree....
    carbon is used extensively in; professional race cars, military applications, nasa and other applications where rigorous stress and impact resistance is required
    ... and budgets are unlimited.

    Quote Originally Posted by dan51
    I don't think Santa Cruz, Trek, and Specialized (three of the biggest bike manufacturers) would be building 6" travel bikes out of it.
    They are building with carbon because they can charge people $8000 for one. Right out of the box, there is an obvious concern over impact resistance. Trek's new "Carbon Armor" shows there is an obvious need for protecting the stuff from impacts. Or maybe it's like those rubberized orange seals that come with Enduro bearings -- just to make people feel better.

    Is the Mojo's magic in the fact that it is carbon fiber or the linkage design? It's not like you're riding down the autobahn and the carbon fiber is soaking up all the imperfections in the road which turn into vibration so you never notice them. You're ripping down Braille and still feeling a lot of the sensations provided by the trail through the bike (hopefully). I don't see what advantages it offers other than being the next cool thing at a premium price in the MTB application.

    I do remember the walk back to 9x35. It sucked. I never said aluminum was indestructible, as I have proven several times it isn't. My fear is that when carbon fiber does fail, it will be in a much more spectacular way resulting in greater injury. While MTBing is risky in general, I'd rather fail at a jump and get hurt than have my bike implode on it's own plastic seams while JRA and send me face first into the ground.

    Sorry, I just don't see the need for carbon fiber when you have six inches of suspension travel to absorb bumps, hits and drops while out on the trail. On a road bike, I'm sure it provides a much stiffer (again, how well can a 6" bike pedal?), smoother ride all in a lighter package... but give me metal for riding in the dirt.

  11. #11
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    Quote Originally Posted by dan51
    How many aluminum frames have you broken?
    Remember walking 2 miles at Saratoga Gap when your aluminum Stumpy failed?

    In the end everything will fail given the right circumstances, everything.

    Get what you want, it's all personal preference. I was a carbon hater until I got one, and I absolutely love it. My carbon frame fear is over.
    If carbon was truly an inferior material I don't think Santa Cruz, Trek, and Specialized (three of the biggest bike manufacturers) would be building 6" travel bikes out of it. That being said, I will never run a carbon seatpost or handlebar on a MTB. It's just in my head to think that they are inferior and will fail in a major way.
    Carbon is great as a structural element. The issue is with impacts, dings etc. How much "frameskin" are you running on your Mojo? If you don't slather the bike with rubberized tape, any impact is going to really mess up the paint/clear coat and possibly top layer of carbon.

    The way I treat my bikes (read abuse) I decided I'd rather have aluminum. This after having owned a couple Kestrel carbon MTB's, GT carbon, Giant carbon and even an Ibis Mojo.

    Quote Originally Posted by dan51
    I wonder how many people that say never get a carbon frame are running carbon seatposts or handlebars.
    A) carbon bars to make me a little nervous - but B) they don't take rocks like chainstays and downtubes do, so they aren't as likely to get the stress fractures - unless you crash on them or overtighten your stem bolts.
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  12. #12
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    Quote Originally Posted by iheartbicycles
    How much "frameskin" are you running on your Mojo? If you don't slather the bike with rubberized tape, any impact is going to really mess up the paint/clear coat and possibly top layer of carbon.
    I'm probably running the same amount as most other people.
    I chose to put frameskin on because the bike is so beautiful I didn't want to get it dinged and scratched, not because I thought it would make it a stronger bike. I use the stuff on aluminum frames as well to prevent scratching and cable rub marks. The only paint advantage aluminum has is if it gets anodized. Paint is going to chip no matter what, whether it's on steel, carbon, or aluminum. Take a look at Shiloh's painted Stumpjumper. It's been chipped so bad it's practically raw now.

    I can understand the question of reliability when it comes to impacts. Every time I have a rock hit it hard I immediately pull over and check it out. I'm constantly going over the frame looking for cracks and am always disappointed (yet also impressed) to never find any.

    The point is, I like my bike and it has changed my view on carbon. And my views were exactly like jdub's.

    Maybe we should get a 7 hour spot on CSPAN so we can have pro and anti carbon sides debate it...in the end nothing will change.

    I'd love to see Trek or Specialized do an impact test. Put an aluminum and carbon Remedy/Enduro side by side and have them each take the same hits in the same spots, then throw them in their stress test machines to see which fails first. That would probably be the only way to fairly compare the two materials.

  13. #13
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    Trek runs an extra layer of material through the tubes of their Remdy called "Caron Armor" that is supposed to guard against blunt strikes. They also use a plastic guard right under the down tube for even more protection.

    http://www.trekbikes.com/us/en/bikes...medy/remedy99/

    Plus if the carbon does fail on a Trek, they're gonna take care of you

  14. #14
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    just my opinion, but I look at it this way. If $$$ is an issue,

    AL bike + really good fork and wheels >>> carbon bike with average wheels & fork for the same price. You might even have more left over for other better components.

    carbon is nice and probably better (but not by a whole lot). Its a very expensive premium cost for what you get. dan is right about whatever can break a carbon frame will probably also break an AL frame.

  15. #15
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    Here is a video from niner http://www.ninerbikes.com/fly.aspx?l...true&taxid=281 takes a while to load. The Carbon fork was actual hit more times that the Steel. You can pick it apart if you like. But I found it interesting. BTW thin XC (AL) frames dent very easily too!

    Someone made a good point about riding a squishy 6" bike already - so I'll agree. All thing being equal; I don't think I would notice a difference switching out my (M5 AL) frame on my 5.5" SJ to carbon.

    But my S-works Epic (2010 carbon) gets a huge headset and BB area and the diff between that and the (AL) model is noticeable.
    Last edited by diver160651; 02-28-2010 at 09:42 AM.
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  16. #16
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    Another bike demo season has started. Go check the bikes out yourself. I didn't think many 6" travel bikes offer a carbon version though. If you are willing to consider 5.5" travel bikes, that will open a lot of carbon doors for you. With some trail bikes, I can feel the drastic differences in riding between carbon and AL. I don't pay much attention to the robustness of the material though. (Not saying others shouldn't.)

    A few shops that I know who do demos include:
    - Passion Trail Bikes (March 6/7)
    - Trailhead
    - Calmar
    - Sunshine Bicycles
    - Mike's Bikes
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  17. #17
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    Quote Originally Posted by jdubsl2
    On a road bike, I'm sure it provides a much stiffer (again, how well can a 6" bike pedal?), smoother ride all in a lighter package... but give me metal for riding in the dirt.
    Check out bustedcarbon.com. That site should be enough to scare anyone away from carbon road bikes and handlebars. Those 2 items take up about 90% of the posts. About 90% of the posts seem to be from people driving their bikes into garage doors or getting run over by cars.

  18. #18
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    Quote Originally Posted by dan51
    Check out bustedcarbon.com. That site should be enough to scare anyone away from carbon road bikes and handlebars. Those 2 items take up about 90% of the posts. About 90% of the posts seem to be from people driving their bikes into garage doors or getting run over by cars.

    holy !@!@#!@#





    This guy could've made it out.


  19. #19
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    Quote Originally Posted by jdubsl2
    Trek's new "Carbon Armor" shows there is an obvious need for protecting the stuff from impacts.
    Or it shows that the cycling community has a fear of something which may or may not be real, and Trek's marketing department found a way to profit from it.

    Why not go with an Al front triangle and CF rear triangle? Something like a Yeti 575 maybe? Jenson has some frames on sale right now. Although, I agree with the previous posters about the need for CF on a big travel bike. I only have an XC bike, but think if I bought a bigger travel bike, I'd want a stiff frame with very little flex, since the suspension is going to soak up the bumps.

  20. #20
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    Quote Originally Posted by maleonardphi
    Or it shows that the cycling community has a fear of something which may or may not be real, and Trek's marketing department found a way to profit from it.

    Very possible. However I can tell you first hand that when carbon meets a rock bad things can happen even with the best carbon manufacturers...
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  21. #21
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    i can't speak for everyone, but i love my carbon s works stumpjumper...i find it to be as advertised--light, stiff, good handling and good looking. only problem is expense, and there's just no way around that one. the frame is warranted for life from specialized so i'm not concerned about it breaking, and i'm sort of a wimp anyway. i upgraded from an aluminum s works stumpy and noticed the difference immediately....it was just better in every way, at least for me.

  22. #22
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    My 2005 Enduro is aluminum and I've put it through some mean ****. Still not broke. Sure, it weighs 29 pounds.

  23. #23
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    Looking at the applications for carbon composite materials, there are basically two variants: Either it is a highly stressed structural component, like in a F1 car, a racing yacht or David Copperfield's flying harness, or it is supposed to take some abuse, like a bullet proof vest or skid plates for dirt bikes or rally racing cars. It's never both at the same time, which is why I have a no-carbon policy for my bikes.

    C>

  24. #24
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    I apologize in advance for this general statement, but I think a lot of people who haven't tried carbon frames are afraid/biased to do so. I've seen dozens of threads on here where people post pics of their broken carbon bars or seatpost. Well, that's just what happens when carbon fails, it breaks. However, when you take a spill and bend an aluminum handlebar or seatpost, isn't it 'broken' or in need of replacement?. Granted, the thought of handlebars (specifically carbon) breaking, while ripping down something like repack, is pretty darn scary.

    The reason I'm using handlebars/seatposts as an example here is because there really aren't too many threads that are overwhelmingly in support of carbon mtb frames failing prematurely [yet?]. Personally, I own a mojo and I love it for what it's intended to be used for (not a DH/DJ bike). I can't justly say that I won't ever break it but I do know that in the past (bmx days) I have broken aluminum, 4130 cromoly and steel. The frames always broke at the welds and I've snapped cranks and stems clean in half. That's in addition to the many parts that got bent.

    I'm not an advocate of carbon or aluminum but I'm just saying that one shouldn't be so quick to rule out a carbon frame until they've tried it.

  25. #25
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    Quote Originally Posted by csuder99
    Looking at the applications for carbon composite materials, there are basically two variants: Either it is a highly stressed structural component, like in a F1 car, a racing yacht or David Copperfield's flying harness, or it is supposed to take some abuse, like a bullet proof vest or skid plates for dirt bikes or rally racing cars. It's never both at the same time, which is why I have a no-carbon policy for my bikes.

    C>
    This is true. The only product I know of (other than bike frames) that uses carbon both as a structural element and one that takes beatings, is carbon baseball bats.

    The way they do this is by basically building one bat inside of another - the outside takes the hit, the inside acts as the structure of the bat. This isn't done in bike frames.
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  26. #26
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    I just reread the OP. You're only entering your third year of riding? And you're hella better than me. Dammit. I take back what I said before.

    You need a play-doh bike with lead spokes and rims. Even the playing field up a bit.
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  27. #27
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    Quote Originally Posted by iheartbicycles
    This is true. The only product I know of (other than bike frames) that uses carbon both as a structural element and one that takes beatings, is carbon baseball bats.

    The way they do this is by basically building one bat inside of another - the outside takes the hit, the inside acts as the structure of the bat. This isn't done in bike frames.
    There is also a good selection of single wall carbon bats -- the double wall bats are starting to fade do to league restrictions etc..
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  28. #28
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    My one year old aluminum 29'er single speed hardtail has a crack in it. (and definitnely not a 'cheap' frame either). I ride and race nothing but XC on it.

    everything breaks.

    I have a carbon frame on order.
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  29. #29
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    El Castigador,

    I think this thread is going in circular loops -- I read a couple of good points and even few ridiculous statements. Heck, somebody thinks carbon isn't stiff enough for them.. Darn, just the other day I heard Lance saying the same thing as he averaged 15mph at Leadville! OK not really, just attempting to point out just how off base some statements can be.

    In the end it might be wise not to listen to me, or anyone else. Just pick the frame that YOU WANT. If you think that carbon frame is sexy - get it.. or your always going to wish you did. If you can't afford it, don't sweat you'll have a blast on the light weight AL counterpart!

    good luck!
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  30. #30
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    Get the bike you like.

    With an aluminum bike you will get a much better selection of frames for better price. So far full suspension carbon bikes had been not much lighter - if at all - and pricier. As far as durability, aluminum is easier to check for damage, so you worry less.

    You do not care as much about "dampening" in a full suspension frame, you have suspension for that. Stiffness will be a function of design and pivots, not of material. Most 6" bikes are plenty stiff. A very popular carbon trail bike - Ibis Mojo - is not known for stiffness.

    If I was building a new bike from scratch to replace my Coiler, I would either go back to Kona, as they are perfectly functional for the price, or get a Knolly frame for more money. Or maybe Pivot. Or Ventana (there was a good sale on Terremoto frames). Seems like my choices are all aluminum.

  31. #31
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    Lots of interesting perspectives, yet I am not yet convinced either way.

    A little more info:

    I already know which frame I'll be buying, just not the material. The difference in cost between the two materials isn't really that much, and since I've been squirreling money away for a good long while, it's not a concern at all.

    I ABSOLUTELY want additional dampening, even on a 6" bike; I like a lot of squish on the downhills. My only reservation about carbon is its impact resistance. I'm not as concerned about a catastrophic frame failure as I am about it getting smacked by a babyhead, or Chuck knocking it into a granite boulder, and feeling insecure about its integrity thenceforth.

    How much abuse can a carbon frame really take? I'd probably end up putting some of the non-skid looking stuff that comes on the Remedys on the downtube anyway.

  32. #32
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    Quote Originally Posted by El Castigador
    How much abuse can a carbon frame really take? I'd probably end up putting some of the non-skid looking stuff that comes on the Remedys on the downtube anyway.
    Brian Lopes has been riding/racing the Mojo for 2-3 years now and has yet to break one.
    Granted he's probably one of the smoothest riders on the planet.
    Troll the Ibis forum and look for any posts with broken Mojos. They do exist, but they are few and far between. Ibis usually has the replacement frame in the mail within 24 hours too.

    Sounds like you're looking at a Remedy. I'd be hesitant only because the carbon Remedy is so new. I like to give things some time and let others work the bugs out before I buy. They may have layup issues they don't yet know about. In a year the frame should be dialed to perfection. Same would go for aluminum frames. Both Justins in this thread broke their aluminum Remedys, and they were both first round production IIRC.

    from GoPro on Vimeo.


  33. #33
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    Quote Originally Posted by El Castigador
    I ABSOLUTELY want additional dampening, even on a 6" bike; I like a lot of squish on the downhills.
    I am not sure I understand how those two properties are related. If you like plush - you can get a coil shock and a plush fork (I really like Wotan for that, and also Van36) and suspension that does not need much of a "platform". I just turn pro-pedal completely off on DHX coil and do not care about a little bob. 6" carbon frames are quite thick, not like they are pliant to the level of 1kg weenie hardtails anyway.

    The fact that you ask this question means you would keep worrying in the back of your mind anyway. Probably the best thing is to get whatever you are comfortable with - it is a toy after all.

  34. #34
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    Quote Originally Posted by dan51
    Sounds like you're looking at a Remedy.
    2010/2011 Enduro actually Dan.

  35. #35
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    Quote Originally Posted by Curmy
    I am not sure I understand how those two properties are related. If you like plush - you can get a coil shock and a plush fork (I really like Wotan for that, and also Van36) and suspension that does not need much of a "platform". I just turn pro-pedal completely off on DHX coil and do not care about a little bob. 6" carbon frames are quite thick, not like they are pliant to the level of 1kg weenie hardtails anyway.

    The fact that you ask this question means you would keep worrying in the back of your mind anyway. Probably the best thing is to get whatever you are comfortable with - it is a toy after all.
    Jeeze, focus on the question: is carbon's susceptibility to impacts enough of an issue to rule it out as a 6" trail bike.

    I am already on a 6" enduro and ride it like a cross country bike, which is how I'll be riding his new bike. I like the vibration dampening and stiffness that carbon offers. My monkeylite DH bar was a noticeable improvement over the stock aluminum bar.

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    that seemed really nasty -- go to the niner site and see the impact video that was posted earlier on this thread - call specialized, call a friend but you should not be so nasty -- to Curmy
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  37. #37
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    Quote Originally Posted by El Castigador
    2010/2011 Enduro actually Dan.

    Check into Specialized's warranty. I've heard they've gone to 1 year warranty on swing arm's. I've also heard a few horror stories about Specialized business practices when it comes to warranty lately. This would concern me since I broke every model of Enduro I owned from 2000 to 2006 when I finally gave up on them

  38. #38
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    Aluminum is well-known to have a finite fatigue life. Fatigue is tested by rigging an object of a given material (handlebar, bike frame, etc.) onto a jig that subjects it to cyclical stresses until it fails.

    A specific example would be the head tube test, whereby the jig connects to the bike like a fork's steerer tube and flexes back and forth until something breaks. Aluminum bikes ALWAYS break, eventually. ALWAYS. It's just a question of how many fatigue cycles the aluminum will survive.

    A lower fatigue load relative to the strength (beefiness) of the frame will increase the number of fatigue cycles to make a frame last long enough for the majority of riders, but given enough use, every aluminum frame will eventually fail. This has been demonstrated over and over and over. It's This is the definition of "finite fatigue life," and aluminum's eventual failure when subjected to cyclical loads is not a quest of "if," but a question of "when."

    Some materials, such as steel, have an infinite fatigue life, which means...
    Continued here: http://marinmtb.com

  39. #39
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    Mountainbike magazine did a pretty lengthy article on carbon this month.
    http://mountainbike.com/carbon

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    Quote Originally Posted by El Castigador
    Lots of interesting perspectives, yet I am not yet convinced either way.

    A little more info:

    I already know which frame I'll be buying, just not the material. The difference in cost between the two materials isn't really that much, and since I've been squirreling money away for a good long while, it's not a concern at all.

    I ABSOLUTELY want additional dampening, even on a 6" bike; I like a lot of squish on the downhills. My only reservation about carbon is its impact resistance. I'm not as concerned about a catastrophic frame failure as I am about it getting smacked by a babyhead, or Chuck knocking it into a granite boulder, and feeling insecure about its integrity thenceforth.

    How much abuse can a carbon frame really take? I'd probably end up putting some of the non-skid looking stuff that comes on the Remedys on the downtube anyway.
    As with all big purchases check references. Talk to people who own the bike you're interested in. Try to find someone who has owned the bike for a long time and ridden it hard. Inspect it and see how it's holding up.

    "beaverbiker" here on mtbr rides the Specialized you're looking at. Go find him.
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  41. #41
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    Quote Originally Posted by El Castigador
    Jeeze, focus on the question: is carbon's susceptibility to impacts enough of an issue to rule it out as a 6" trail bike.
    Do you honestly expect a bunch of folks here give you a better answer then bike designers who have decided to build and sell a bunch of carbon 6" trail bikes?

    They believe it is fine and worth the benefits and premium price.

    I believe that there are no real benefits to justify the marketing claims, as suspension design and especially shock choice and tuning are more important - but then I ride a ostensibly terrible, outdated suspension design that is supposed to throw me off on every bump, while the mega buck quadruple link multi squat instant tracking gizmos that are flickable, performance tuned, vertically compliant, simultaneously stiff and pliant depending on your mood and phase of the moon, just pedal themselves to the top while you wait. So what would I know..

  42. #42
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    Quote Originally Posted by dan51
    Mountainbike magazine did a pretty lengthy article on carbon this month.
    http://mountainbike.com/carbon
    if you read the article in the mag itself, they say that for 6" + bikes you would have to singnificantly increase the layup of carbon at the HT to deal wiht the leverage of long travel forks. that would negate any weight savings of carbon and increase cost.

    I personally don't want anything to do with carbon. If you only ride buff trails, then maybe carbon is for you. BUT If you ride hard on rock infested trails, Aluminum will outlast Carbon.

  43. #43
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    Quote Originally Posted by ThePunisher
    BUT If you ride hard on rock infested trails, Aluminum will outlast Carbon.
    Why is that?

  44. #44
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    Quote Originally Posted by diver160651
    that seemed really nasty -- go to the niner site and see the impact video that was posted earlier on this thread - call specialized, call a friend but you should not be so nasty -- to Curmy
    No nastiness inended, just trying to keep the convo focused.

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    Quote Originally Posted by alexb650
    Why is that?
    get the latest issue of Mountain Bike and read the article. it's really informative.

    If you really ride hard; sooner or later you will crash. regardless or the bike's material, if you carsh in rocks it will leave a mark. A dent on aluminum to me is less worisome than a chip in carbon.

    if you ride tigh single track with boulders; sooner or later you'll end up catching one of them with your stays.

    Lastly, have you even seen bikes after a full summer of high mountain riding in rocks? the downtube looks like it's been shot by a shot gun (eg many small dings and dents). I've even seen some with big dents near the BB.

    But will get the job done - but I personally feel safer on an Aluminum frame for this particular kind of riding.

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    Quote Originally Posted by ThePunisher
    get the latest issue of Mountain Bike and read the article. it's really informative.

    If you really ride hard; sooner or later you will crash. regardless or the bike's material, if you carsh in rocks it will leave a mark. A dent on aluminum to me is less worisome than a chip in carbon.

    if you ride tigh single track with boulders; sooner or later you'll end up catching one of them with your stays.

    Lastly, have you even seen bikes after a full summer of high mountain riding in rocks? the downtube looks like it's been shot by a shot gun (eg many small dings and dents). I've even seen some with big dents near the BB.

    But will get the job done - but I personally feel safer on an Aluminum frame for this particular kind of riding.
    I got the new MBA last week and I haven't had a chance to read it yet, so I can't add anything to the article you're referring to.

    I do ride hard and I do crash on occasion but I can't say that I would rather have a dent in AL over a chip in CF. If you dent an AL frame at the top of the down tube and it's creased, the frame is pretty much toast, right? So, on either frame, It would depend on where it was and how severe.

    As to your last point, I do know what you're talking about. Looks like the bike got sprayed on the underside. I don't know enough to say how much that will effect the integrity of a frame--again, it depends on whether it's cosmetic or structural damage.

    I meantioned earlier in this thread that I'm not gung ho for AL or CF and I'm trying to be as impartial as possible. I'm also not a very active member of this site but I decided to chime in because the OP was getting tons of negative feedback about CF from people who have never owned a CF frame and probably never seen one that's broken.

    My advice to the OP, try searching, "carbon frame broke," "carbon frame cracked" or things of the like and see what you find. I went through this before buying a Mojo and I couldn't find enough to suggest that carbon frames are faulty. Or, call your LBS and see how many carbon frames they send out for warranty and for what reasons.

  47. #47
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    Quote Originally Posted by alexb650
    I got the new MBA last week and I haven't had a chance to read it yet, so I can't add anything to the article you're referring to.
    FYI, it's not in MBA it's in "Mountain Bike".

  48. #48
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    You guys are making me nervous!

    I have Carbon wheels, cranks, seat post, steer tube, crown, bars and frame --

    I'm more of a climber; not a guy who table tops on my way down downyvile - I am fairly light on my gear. I have owned about 8 wheel sets in the last year, the only failures have been free-hubs. . Yet, I have I had 3 al frames fail, two with cracked head tubes and another with a chain stay --

    Everything breaks -- and that bustedcarbon.com thing is kinda funny - maybe all it really shows is that people who purchase carbon items can't drive well.

    When I was a sponsored MotoX guy I had less worry about holding the throttle wide open at the 15 second turn of the board. But before that, it freaked me out because I didn't have the ability to fix the motor cheaply. If you have the cash and body reserves to ride near 100% down the hill, crash and replace gear; it doesn't matter what you run does it?

    Personally, I am much more worried about my broken body than my plastic bike.. I am already sporting an artificial joint and have had to many broken bones to count -- so I always try to ride no more than about 75-80% of max speed, even then skeggs punched me in the ribs a few months ago -- more broken body parts!

    what the hell, get the carbon you'll break first
    Last edited by diver160651; 03-02-2010 at 04:06 PM.
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    You guys are killing me. Pound for pound, carbon is stronger than aluminum.

    If you build up a two identical frames of the same weight, one from carbon and one from aluminum, the carbon frame will be stronger.

    The reason why carbon gets a bad wrap in the bike industry is because lots of frame manufacturers try to build two identical frames of the same strength, but use less material in the carbon frame to make it lighter. I think GT these days has a all carbon DH bike that weighs in the same as an aluminum DH bike and is very durable. Carbon doesn't have to be just for XC frames or short travel forks.

    As far as scratching a carbon frame on rocks, you guys do know the top layer with that cool carbon fiber looking weave is mostly cosmetic right? You actually need to gouge a carbon frame or bars or helmet or whatever pretty deep to make it unsafe.

    All that said, I have no idea if trek, spesh, ibis, SC or any of those other dudes are skimping too much on material just to make the frame lighter and justify the blingin price tag or not.

  50. #50
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    Quote Originally Posted by bdamschen
    You guys are killing me. Pound for pound, carbon is stronger than aluminum.

    If you build up a two identical frames of the same weight, one from carbon and one from aluminum, the carbon frame will be stronger.

    The reason why carbon gets a bad wrap in the bike industry is because lots of frame manufacturers try to build two identical frames of the same strength, but use less material in the carbon frame to make it lighter. I think GT these days has a all carbon DH bike that weighs in the same as an aluminum DH bike and is very durable. Carbon doesn't have to be just for XC frames or short travel forks.

    As far as scratching a carbon frame on rocks, you guys do know the top layer with that cool carbon fiber looking weave is mostly cosmetic right? You actually need to gouge a carbon frame or bars or helmet or whatever pretty deep to make it unsafe.

    All that said, I have no idea if trek, spesh, ibis, SC or any of those other dudes are skimping too much on material just to make the frame lighter and justify the blingin price tag or not.
    I'm not a materials engineer, but I know Carbon is stiffer but I'm not convinced it's stronger.

    yeah okay, maybe the surface layer is only cosmetic, but once you hit that hard on a rock, what reassures you it's still structuraly sane? That's the problem with carbon, once it's compromised (in any way) it's pretty much useless.

    A crack or even seemingly benign surface penetration renders it untrustworthy. A simple ding on aluminum does far less to the integrity of the frame. Don't get me wrong, it's strong, however, it has it's drawbacks.

    carbon fiber is just that: FIBER. It has high tensile strength, but like mentioned in the Mountain Bike article, the fibers will break when stretched which constitutes a weakness.

    anyway - this is just my $0.02. Like I said, nothing wrong with Carbon bikes - just be aware of what you ride and keep a close eye on the frame. Especially the head tube and areas exposed to rocks.
    Last edited by ThePunisher; 03-02-2010 at 06:43 PM.

  51. #51
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    Quote Originally Posted by ThePunisher
    A crack or even seemingly benign surface penetration renders it untrustworthy. A simple ding on aluminum does far less to the integrity of the frame. Don't get me wrong, it's strong, however, it has it's drawbacks.

    carbon fiber is just that: FIBER. It has high tensile strength, but like mentioned in the Mountain Bike article, the fibers will break when stretched which constitutes a weakness.
    A crack in an aluminum frame is also bad and renders a frame untrustworthy.

    Fiber having a high tensile strength just means that it won't stretch until it has reached its breaking point. Aluminum will deform slightly at less pressure before ultimately breaking. The breaking point of carbon fiber is much higher than aluminum.

  52. #52
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    Quote Originally Posted by bdamschen
    You guys are killing me. Pound for pound, carbon is stronger than aluminum.

    If you build up a two identical frames of the same weight, one from carbon and one from aluminum, the carbon frame will be stronger.
    I am not sure "stronger" is a proper term here. If by stronger you mean resistant to stress - yield, tensile and fatigue stress, then sure, proper made carbon is by far stronger. Impact strength - I am not sure. But that is only a part of frame durability. Plasticity for example (ability to make a dent without breaking apart) is another factor. Deflection - how far will it bend without breaking - is another.

    I have little doubt that most everything that is on sale is strong enough for its purpose.

    My personal semi-educated concern about the modern state of this technology is mostly about inspection for damage. When picking up a hardtail for adventure racing I chose titanium as I think that after tossing my bike down a rocky slope at night I will be able to tell the damage on a titanium frame and keep riding it, and I would not be so sure about a carbon one. Even if the carbon one is twice "stronger" - it still breaks.

  53. #53
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    Quote Originally Posted by Curmy
    I am not sure "stronger" is a proper term here. If by stronger you mean resistant to stress - yield, tensile and fatigue stress, then sure, proper made carbon is by far stronger. Impact strength - I am not sure. But that is only a part of frame durability. Plasticity for example (ability to make a dent without breaking apart) is another factor. Deflection - how far will it bend without breaking - is another.
    From what I remember, or think I remember about carbon fiber is that in the realm of plasticity- carbon is brittle and has none it just goes straight to a breaking point, but aluminum's breaking point even after denting, is still lower than properly constructed carbon fiber. So sure aluminum would dent before breaking, and carbon would just break, but the aluminum would dent and break long before carbon.

    Deflection also sort of falls into the same realm. Carbon Fiber won't deflect much, but it will take a lot more force to break it. It will remain stiff the entire time up until failure. That failure point should be much higher than a comparable aluminum frame if I remember right.


    Good point on inspection though. I think I'd avoid a carbon frame for adventure racing just on that and carbon's susceptibility to moisture if not properly laminated. For big hits on something like a 6" AM ride or even an 8" DH bike, I'd probably feel pretty confident on carbon.

  54. #54
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    I bet this same discussion happened years ago when aluminum was the next bike material.
    Some folks probably said it will never work and they will only ride steel until they die, while others decided to give it a try.

    I bet in another 10 years, we'll be having the same discussion, but stating "I won't ride anything but carbon. That new [insert technology] is [insert fault]."

    I think all the materials have their place, and carbon is trying to prove it's useful in a 6" AM bike now.

  55. #55
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    Quote Originally Posted by El Castigador

    Factoring in the weight savings, the increased stiffness, and the better dampening of carbon, it seems to be the clear winner in every category save one: impact resistance. I'm actually pretty concerned about this since I seem to crash more frequently than most of the people I ride with.

    Should I stay with aluminum?
    You're never going to get an answer for which is better. However, I really don't think you need to stress about a carbon frame as much these days. Quality carbon frames have come a long way. Plus, you say your'e mostly XC, so I really doubt you'll be putting yourself in situations very often where you'll have a hard enough impact to really destroy the frame. The rear triangle on the Enduro is aluminum, so what impacts are you really worried about for the front triangle? If you're worried about cosmetic damage to the down tube, just put some 3M tape on it. Carbon can take blunt impacts extremely well. A sharp edged rock, however, can possibly score a carbon frame beyond the cosmetic layer. Note, this type of impact will also damage aluminum. BUT, these types of damage can be repaired by carbon frame builders. I know Calfee offers a repair service.

    Everyone can come up with tons of "what if" scenarios. What are you realistically going to be putting your bike through?

    Just curious, did you get to ride both bikes to compare the vibration dampening? I know you mentioned that's a huge plus for you.

    I own aluminum bikes, and I've ridden carbon bikes. I wouldn't hesitate to buy a carbon frame. But I'm also a lightweight and ride mostly XC. I do crash, but most of my crashes result in scrapes rather than breaks.

    The easiest solution? Just stop crashing.

  56. #56
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    Quote Originally Posted by dan51
    I bet this same discussion happened years ago when aluminum was the next bike material.
    Some folks probably said it will never work and they will only ride steel until they die, while others decided to give it a try.
    "Yeah, you stick with your fancy Coke can frame. 4130 all the way, baby!"

  57. #57
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    Quote Originally Posted by dan51
    I bet this same discussion happened years ago when aluminum was the next bike material.
    Computers and internet forums weren't around back then, but it was definatley a topic that was discussed. Remember the PK Ripper? Everyone always knocked it because "aluminum is weak and it will break." However, that had more to do with the welding technology than anything else and they've improved on that problem since then.

  58. #58
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    One of the TROGS had a mojo, after the third time the frame broke (different issues each time) he sold it and will never go back.

    I know carbon can be quite solid but I'm not sure it's there yet in the cycling industry.

  59. #59
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    Screw carbon and aluminum .........get Ti

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    Bamboo is hot right now -- no kidding

    BTW wish I still had my steel 83' SJ or my 3 speed 81 downhiller ... Steel is so cool! Can't tell you how easy it bends BACK into place ;-)
    Jt

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    Bamboo is hot right now -- no kidding

    I know their hot right now as flooring, he he he....

  62. #62
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    Quote Originally Posted by bdamschen
    Fiber having a high tensile strength just means that it won't stretch until it has reached its breaking point.

  63. #63
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    aren't wings designed to flex?

  64. #64
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    Quote Originally Posted by Pimp-Al
    Bamboo is hot right now -- no kidding

    I know their hot right now as flooring, he he he....
    I saw this documentary on the discovery of a new planet called Pandora with a large deposit of new mineral called Unobtanium. Maybe look into that?

  65. #65
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    Quote Originally Posted by beaverbiker
    ***Important factual information***

    Oh great, someone who knows what they're talking about. Fun's over.


    Time to ditch all the arm chair engineering and go back to practice opening a beer with a CD.

  66. #66
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    Quote Originally Posted by dan51
    I bet in another 10 years, we'll be having the same discussion, but stating "I won't ride anything but carbon. That new [insert technology] is [insert fault]."
    Quite possible.

    Look at Boeing 787. It has been delayed since somebody was not doing layup of the wing to fuselage assembly quite right - if I remember correctly. They had to fix it with some extra layers.

    Now - do you trust some underpaid underage employee in a Chinese village to layup your headtube just right?

    I would rather trust some underpaid underage welder - that is a more developed production technique as of right now.

    Cheaper and works just fine - what's not to like? In any case - for things like handlebars carbon is certainly already well proven, we probably would be able to say the same about frames in a few years - they are just showing up..

    My only experience with composites was watching my collegues design and test a support structure for a sattelite experiment. About as cutting edge as it was a few years ago. We gave up and went with a metal construction - could not make it reproducible enough. Of course that bit was designed for operation in vaccum and withstanding launch, but then it was not made in a Chinese village either..
    Last edited by Broccoli; 03-03-2010 at 01:02 PM.

  67. #67
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    Quote Originally Posted by Curmy
    In any case - for things like handlebars carbon is certainly already well proven, we probably would be able to say the same about frames in a few years - they are justs showing up..

    .
    I might be wrong about my facts -- the I think the point is will be clear.. In 1975 your statement would have been perfectly placed as the first carbon tubes and lug frames were showing up -- the bond wasn't all that good until TREK got involved, About a decade later, luggless construction we use today was introduced. That was about 25 years ago or about the same time of the first suspension MTBs! Trek has been making carbon MTBs for over 15 years! One of my riding buddies still rides a old, old OCLV HT rim brakes and all - it is a rocket (however he is slow ;-) )

    I think it was about 20 years after CF, that hydro discs were available.. Should we wait until the brakes prove themselves ;-)

    Oh
    Jt

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    since i got a C in all my material science engineering classes, i'll ask you a few questions, mainly for my own eddification:

    to what extent can FEA be used w/ a material like carbon fiber (if at all) given how complex and non-homogeneous it is? seems like applying FEA to any sort of alloy would be a relative no brainer. is carbon fiber primarly tensile strength (like steel) or compressive (like concrete), or is it both (i.e. the fiber strands provide tensile resistance, and the epoxy/resin provides compression resistance)?



    Quote Originally Posted by beaverbiker
    Composite materials don't yield like homogeneous metals. That means, at a certain point in the stress strain plot, the composite material will break and not take any more strain. Homogeneous metals will keep straining after the yield point, but will not take any more stress.

    If you guys really want to learn something and not just listen to people blabbing on the internet, study up on young's modulus and how they differ between composite materials and metals. You'll understand where all these theories about composites come from.

    The main thing with composite materials is that the material does not have equal material properties in all directions (non-homogeneous). With homogeneous materials (almost all metals) you only have to worry about the thickness. With composite materials, you have to worry about the thickness and which direction the load bearing fibers are positioned within that thickness.

    All these extra variables make composite material that much harder to analyze for various load cases, so the engineers heavily rely on testing. If you wanted to know how much the tip of a metal beam would deflect if you pushed down on it with a given force, you could calculate that by hand without a calculator. If you wanted to do the same thing for a composite beam, you'd have to know the exact lay up (not just material average density, remember it's non-homogeneous) and be pretty good with a computer and super up to par on your linear algebra. You guys should all call these big bike companies and ask them how many hours they spend per bike breaking them on the test machines and using that data to better the design instead of just going with the original prototype tooling and saving money.

    On that note, I run a composite skid plate on my dirt bike and trust that thing to keep my engine from getting blown up when I'm 50 miles from camp and doing 40mph through the worlds gnarliest rocks.
    94 Specialized Rockhopper

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    Quote Originally Posted by Curmy
    Now - do you trust some underpaid underage employee in a Chinese village to layup your headtube just right?

    no, but I would trust some underpaid Taiwanese employee in a Taiwanese village to layup my head tube just right. Those guys know what's up.... as long as they have an american QC engineer riding their butt for anything that goes wrong.

  70. #70
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    Quote Originally Posted by diver160651
    Trek has been making carbon MTBs for over 15 years! One of my riding buddies still rides a old, old OCLV HT rim brakes and all - it is a rocket (however he is slow ;-) )
    I would not have bought a CF hardtail for adventure racing 15 years ago, and I would not do it now. Not much that have changed.

    Quote Originally Posted by diver160651
    I think it was about 20 years after CF, that hydro discs were available.. Should we wait until the brakes prove themselves ;-)
    Hydraulic brakes are around for ninety years - Lockheed used them for cars in 1918. Took twenty years before it was used more widely. They are still only found on expensive bikes.

  71. #71
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    Quote Originally Posted by beaverbiker
    As a side note, if people saw how much load it takes to break a specialized carbon enduro, they'd be spending more time researching doctors and physical therapists than e-debates about strengths of materials.
    Aren't you sponsored by the big "S"? If you crack or damage your bike, you'll probably have a new one the next day. unfortunately it doesn't work like that for everyone.

  72. #72
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    Quote Originally Posted by bdamschen
    no, but I would trust some underpaid Taiwanese employee in a Taiwanese village to layup my head tube just right. Those guys know what's up.... as long as they have an american QC engineer riding their butt for anything that goes wrong.
    Did not work out that well for Boeing and their wings, did it? Don't you like that a 787 you may board soon would have some patches applied.

    Useless discussion anyway. All major manufacturers make fine bikes suitable for their stated purpose, everybody sould just buy what they like. I do not shy away from carbon on a trail bike - I shy away from spending money that I can use for something else.

  73. #73
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    Quote Originally Posted by beaverbiker
    You're right, but do you think I would be risking my life just for free bikes? No way. I've got a job.
    But you certainly would not risk damage to your wallet. I think that was his point. It is a slightly different thought process when you pay a few thousand of your own $ for something that should last you for a few years.

    As far as asking an engineer with experience with composite materials - it just happened that right now I sit next door to a guy who was working on a project I have mentioned above. He agrees with my attitude towards this - to use something else for a while - and he has no vested interest in selling those frames, unlike engineers from bike companies.

    Quote Originally Posted by beaverbiker
    I'd much much rather have a nick in a sacrificial ply than a dent in an aluminum tube that causes a stress concentration and will lead to buckling.
    True, but you can see a dent. I would rather see (or not) a dent in a titanium tube when I keep riding at night, then keep guessing it that nick was superficial or not. But that is me being a cheap bastard.

  74. #74
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    Quote Originally Posted by Curmy
    Did not work out that well for Boeing and their wings, did it? Don't you like that a 787 you may board soon would have some patches applied.

    Now I know I drink a bit more beer and eat a bit more pizza than I should, but I'm pretty sure that even with 10 extra winter pounds that I may or may not have put on, I will come nowhere near putting a carbon DH or AM bike through what a 787 wing might experience.

    I hear ya on cost though. My current AM bike is 4 years old, aluminum and has more flex out back than a 18 year old yoga student. I've hucked it off dumb stuff, crashed it into more dumb stuff and bailed on it over the transition of stuff even dumber still. I'm actually waiting for the day when it disintegrates under me through a rough section. Maybe this year I'll pick up a new frame, but chances are I won't be able to afford carbon.

    If I could though, I'd rock one with out a single doubt in my mind that it would hold up better than the heap I'm currently riding.

  75. #75
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    Wow -- beaverbiker,

    I do feel much better about my carbon wheels now! Thanks...

    Btw I am riding about 500+ miles a month and my own bones and edge of the trail concern me a lot more than engineered parts beating over the rocks.

    Curmy - I don't think anybody is in disagreement with you that AL is cheaper and maybe even a better value. I think we would all agree that someone who only cares to spend a fixed amount, might be better getting an AL frame with great suspension, wheels etc. rather than getting a 4,400 frame/fork and slapping lower end components on.

    That said, I don't think the value issue is on the table for El Castigador. I believe he looking at positives of CF such as increased stiffness, and the better dampening; but is concerned about the impact resistance of CF.

    Taking money completely out of the issue, well designed and built CF wins over thin wall AL..

    The only question El Castigador should ask himself is "If I crash hard enough or unlucky enough to kill a AL or CF frame can I afford to replace it? "

    BTW I was talking about the sram BIKE hydros not cars..
    Jt

    Here are a few Video Trail Guides I shot - just for fun:
    http://destinationproductions.com/cu...PassionTrails/

  76. #76
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    Quote Originally Posted by beaverbiker
    Is that guy the one that was trying to build a support structure out of composites? What happened? I'm not trying to start a war, just curious. I happen to be in the same industry...
    It was hard to build, test and validate and did not bring enough benefits to spend more money on it.

    Quote Originally Posted by beaverbiker
    What your buddy was probably telling you was to stay clear of first generation things as they are not proven and you should "use something else for a while" until they get it dialed in. And I pretty much agree with that for the most part. The thing is, Specialized and other bike companies have been making composite bikes for a very very long time.
    No, for me it is not a question of quality or being a first generation. It is a simple cost/benefit analysis. I do not see any tangible benefits to the long travel full suspension frames so far to justify acquisition and possible maintenance and replacement costs. As I have mentioned in this thread - stiffness seems to be the function of suspension and pivots design - and there are plenty of cheap frames that are strong and stiff enough (my Coiler feels stiffer then Mojo I have ridden, not that I obsess over that). "Damping" does not seem to be of any importance for the wall thickness they use, and given that I have 160mm of plush suspension on both ends.

    For a weenie hardtail I certainly see benefits, but then my very specific use case (adventure racing usage at night) makes titanium my material of choice. It is a more resilient material with a minimal weight penalty, comparable cost, arguably better comfort level of riding and sufficient (for me) stiffness.

    For an AM hardtail I went with steel (TransAm). Slack and strong. I am not aware of CF alternative to that genre of frames.

    Cost/benefits - not paranoia.
    Last edited by Broccoli; 03-03-2010 at 04:39 PM.

  77. #77
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    I have a GT Force Carbon. No issues.

  78. #78
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    Quote Originally Posted by 0gre
    One of the TROGS had a mojo, after the third time the frame broke (different issues each time) he sold it and will never go back.

    I know carbon can be quite solid but I'm not sure it's there yet in the cycling industry.
    Yup... he broke 3 mojos...first one he just flopped over sideways going slow picking his way through a rocky line on a trail and a rock poked a hole in the stay... that's the one I witnessed... the other two I never saw...

    Carbon is for road bikes.
    Trogs: Too Tough for Carbon Fiber

  79. #79
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    When I look at it? It comes down to money. I would love a Fuel 9.9EX or a Remedy 9.9, but I cannot justify the money when I will want something new in 7-8 years. Also you cannot even buy just a frame and put all the cool upgrades you may have on your existing bike onto your new frame. So I am looking at a Camfiled Bro's One frame. I have had only the chance to test ride the oclv frames and they feel sweet. Just way out of the price range. So based on your situation it differs for everyone. If you get caught up in the which one can outlast the other Carbon or AL...you will have a nervous break down. They are both great and if there is a serious problem you will have to deal with the manufacturer. Research that? How is the manufacturer going to take care of you if its on there side?

  80. #80
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    fter yesterday's soggy demo ride at Demo, I'm sold on the carbon Enduro. Even with the 66 degree HT angle, and a 36T "middle" ring, it hammered up the muddy Sulpher Springs easily. It feels quite a bit livelier and stiffer than the Alu version, and feels beefy enough to calm my carbon paranoia.

    Braille was a lot of fun too! The teeter-totter toward the top was a little slow to actuate, so it turned into a 3' roller instead. Pretty sure I would have gone OTB on my old Enduro.

    Anyone know if there are any changes to the frame planned for 2011?
    Attached Thumbnails Attached Thumbnails I need advice, Carbon or Aluminum?-1.jpg  

    I need advice, Carbon or Aluminum?-3.jpg  

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  81. #81
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    None of the above

    For the price of a carbon frame you can pick up a titanium frame on clearance that will last a lifetime, never dent or crack and only be a slight weight increase over aluminum. Yes a titanium frame will be heavier than either and be less stiff, however the flex in it will also make it far more durable. Also the frame being flexible will absorb some shocks from the trail.

    (Note, a thick side walled 7075 aluminum t6 or t651 temper will hold up relatively well also. However you risk denting or fracturing the frame with extended use. Keep in mind lighter frames generally mean easier to break frames. Lighter might sound better but do you think your going to notice a few extra pounds biking compared to a few less pushing.)

    (PS you can pick up titanium frames online for $400-$500)

  82. #82
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    Good info Andrew. I am sure the OP still hasn't made his mind up 2 and a half years later and will appreciate your input.

  83. #83
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    Well, we have to consider catratrophic failure vs. fatigue. Oh, wait, this isn't 2001. Nevermind.
    I don't rattle.

  84. #84
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    How many of us have carbon bikes now? I have and still do

  85. #85
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    Quote Originally Posted by andrew hild View Post
    (PS you can pick up titanium frames online for $400-$500)
    Out of curiosity, where can one pick up titanium frames online for $400-$500? Are we talking new or 10-15 years old? direct from China or US retailer?

    I'm not being contrarian here; I am in the market for 1 & want to know where these deals are!

    Thanks!

    LJ

  86. #86
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    Quote Originally Posted by Shwaa View Post
    Good info Andrew. I am sure the OP still hasn't made his mind up 2 and a half years later and will appreciate your input.
    hey lippy, your on the forum so clearly people are still interested in the topic.

  87. #87
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    TI frames

    Quote Originally Posted by skyno View Post
    Out of curiosity, where can one pick up titanium frames online for $400-$500? Are we talking new or 10-15 years old? direct from China or US retailer?

    I'm not being contrarian here; I am in the market for 1 & want to know where these deals are!

    Thanks!

    LJ
    It has been a while since I have looked, I have seen them before on clearance or holiday sales, you just have to check a lot. Used you will be hard pressed to find one but there out there. Sorry but I don't remember the site names. Yes by the way they were cheap and probably foreign frames.

  88. #88
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    Still on an aluminum frame, but at least a new one now. I'd be riding carbon but I still can't afford it since I have to buy the wife a new frame every time I buy a new frame.

  89. #89
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    Recently, I was considering my steel frame for an aluminum one. It would be a hardtail XC to replace my On-One Inbred.

    Back in the good ol' BMX days, we'd break frames all the time (4130 chromoly). The amount of abuse that our 20" bikes would go through was ridiculous, and I did this as a stocky 14 yr. old. Whenever they would break, we'd grab our allowance money and take it over to Paul Sadoff at Rock Lobster, and for a few bucks, he'd repair them for us and we'd be on our way.

    So, as a 220lb. 38 year old adult who really, really, really likes doing stupid things on MTB's - I've decided that I'm just going to stick with my steel bikes. In fact, I own nothing but steel. There is a weight penalty, and FS doesn't come in steel, but I'm sticking with it. I'm slow as it is, and watching Leopold Porkstacker stay consistent as a local Strava Leader here in SJ, I think that this bike is much better than me.

    However, given my weight, if I were to "upgrade" I'd go with aluminum. Some of you skinny kids, even when riding hard, probably don't stress a frame like I would. Maybe this is just all in my head, but part of the equation is believing your bike isn't going to fail you - and on the mental aspect of MTB'ing I think that means a lot.

    As much as I love the idea of carbon - I think I'd be nervous as a heavyweight riding it. Even if it could handle me, the idea of it breaking would always be on my mind.

  90. #90
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    Quote Originally Posted by Dion View Post
    Maybe this is just all in my head, but part of the equation is believing your bike isn't going to fail you - and on the mental aspect of MTB'ing I think that means a lot.


    Quote Originally Posted by Dion View Post
    FS doesn't come in steel
    You have to go boutique. There are others, but here's two.

    the Product of COTIC cycles : droplink ROCKET

    SyCip Full Suspension Bikes - Handcrafted in Sonoma County, California
    Last edited by IAmHolland; 11-28-2012 at 02:29 PM.

  91. #91
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    A interesting carbon failure.



    Even after seeing that video I'm not concerned with using carbon. Most bikes these days are designed well enough that catastrophic failures are very rare, no matter the material. My biggest issue with carbon is cost and even that is slowly changing. As Dion pointed out the limiting factor is usually the rider and not the bike.

    The choice between carbon or other materials also depends on what you are looking for in a bike. For me carbon makes sense for a hardtail but AL is best for a FS. I have ridden AL HTs for years and they are stiff and strong. It wasn't until I demo'd a carbon HT that I realized how stiff and abusive the ride of a AL HT is. My new XC race bike will be carbon because I want it light and with a softer ride. But Ti or steel will get one a softer ride than AL at less cost than carbon. For a FS trail bike I'll stick with AL, an FS frame needs to be as stiff as possible to let the suspension do the work and not the frame. So either AL or carbon fits the bill. Next is weight, with a trail bike I'm not looking for the lightest thing around. Also, the weight difference is minimal, usually a pound or two. For me the big driver is cost, a carbon FS frame is 1.5-2X the cost of AL. I'd rather use that money for something else wheels, suspension, etc.

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