I was under the impression that ENVE used prepreg for some of their stuff. Could be wrong though. At any rate, wet-layup is just fine for our application, imo.
And Devinci Enters the World of Carbon DH
- Thread starter Downhillbiker23
- Start date
anyone can make stuff out of carbon. making stuff out of carbon and doing a great job of it is where it gets difficult.
maybe some of the enve rims have pre preg in them, i am not sure, but they are not a full pre preg layup anyhow. and 2 sheets of pre-preg soaked in resin defeats the point, no?
all i can say is that i work for a ski brand that offers both prepreg skis and wet layup carbon skis. the pre preg versions are a whole different ball-game compared to the wet-layup. so much more life, power, responsiveness, etc
a prepreg carbon frame would save about 2-2.5lbs, and would literally not flex. it would be revolutionary. the frame would be stiff to the point that everyone would want to run super light wheels and single crown forks to tune the ride, and you would be racing 27-28lb dh bikes that are actually strong and stuff enough to take the abuse. not to mention the bike itself would be dramatically more responsive, so you could run crazy slack angles and not worry about sluggish handling like an aluminum frame has. it would be a different sport. that happens to cost $20k for a built bike.
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So perhaps it's already in use out in the roadie world?.....
I don' think I follow your point?
yeah man, sure is. see the 6lb, $50k road bike build that is floating around.
To you, sure. To me, carbon has been around for more than 10 years (I used to own an STS1000), and there's no reason manufacturers couldn't have been exploring carbon for ultra high end frames back then, rather than now. I find it hard to believe that technology has changed so much that it wasn't even worth pursuing in 2002, and now it's suddenly just cheap enough to offer frames as sky-high prices. To me, it's a "Oh snap, Santa Cruz has carbon, and people actually like it. Wait, Trek has carbon too, and people are excited about it? Quick- let's throw some kind of carbon on our frame, and we can sell just as much." I fully understand that better technology can make for better bikes, but in this case, it doesn't appear to be passed onto the consumer, but rather as Inclag said, into the company's bottom line. If carbon is so much better, and cheaper, then companies should be producing carbon frames for the same cost, or offering their aluminum varieties for less.
That's what I'm saying. Let the pajama wearing faux-pros rock the latest throwaway tech wrapped in $100 bills, and sell a decent, strong, simple frame at a better pricepoint with good geometry and an well-designed shock.
hes saying catalog frames are made like crap. designing a carbon bike right like SC is what makes companies stand out when it comes to CF frames
i never said catalog frames were crap (never said they weren't either), but they certainly won't have the same quality as bits made from carbon fiber experts.
case in point, ricey here is making his own carbon fender in his garage. so yes, anyone can make carbon fiber parts.
First, what makes you say they weren't? You know it takes time to bring products to market, especially with new materials. Trek has been making OCLV stuff for what, 20 years or something, with refinement all along the way.
Also, haven't manufacturers gotten better at using the stuff for bikes? Haven't bike companies been learning what works and what doesn't? Haven't costs come down, making it more accessible for smaller builders? This is bad?
Small builders that use aluminum also took advantage of advances made by larger companies with deeper pockets. Were they jumping on the bandwagon when they switched from steel? Was that also just a marketing scheme with no actual improvement?
I keep coming back to the fact that my real world experience has proven to me that carbon bikes are rad, with real performance characteristics that I like, and that I'm willing to pay for. That's what really matters to me.
You positive on this?
Watched this Trek vid awhile ago and I was certain they were using pre-preg.
http://pelotonmagazine.com/Special-Features/video/10/874/Made-in-AmericaTrek-in-Waterloo
Definitely. I guess I just feel like the MTB industry in particular does not develop things for 10 years, and then finally release them when they are ready. Take a look at the 2010 Boxxer, or the CC angleset...both products with large numbers of problems, but were released to the consumer anyways. I cannot on good faith believe that the anybody in the industry said "Whoa, this carbon thing isn't quite as good as aluminum for DH yet. We definitely need more development time" and not "Hey, it's good enough, sell it and let the warranty department sort it out"
I would disagree that costs have come down, but I haven't run numbers comparing stuff from 01 to 11. Seems to me like things have gotten more expensive. I would agree that things have gotten better though. You certainly get better, lighter, stronger stuff nowadays than you did back then.
Certainly. Hydroforming is so universal it's overdone. And switching from steel is obvious, as aluminum allows similar workability but better material properties. Carbon is even better, but the cost of molds in three sizes, in multiple frames, is potentially huge. I'm not saying carbon is marketing and nothing else. Carbon is good chit, that's for sure. That's not up for debate. I am saying that I'm not certain there is as much value in the material that many people are assigning to it. $1500 more for a frame that saves a pound or two and is _still_ a DH frame that's going to get wrecked and dinged and scratched and dropped just seems so silly to me, beyond what the actual value of having a carbon frame really does for the rider.
They are definitely rad, and if you have the money and want the best, it's probably carbon. I just don't know that the industry isn't following the lead dog just to stay close, rather than striking out and making quality bikes their own way. I think the wilson is a pretty spot-on DH bike. One of my favorite parts is that it's welded in Canada. Jumping on the Carbon spaceship, a little more than a year after the model was released for sale, seems short-sighted, compared to finding other ways to make the frame better, or cheaper. I mean really, if you could get an aluminum wilson for $2000, or a carbon one that's $4500 but weighs a pound less, is there really that much logic to go for the carbon one?
It just seems like DHers are still spending money to try to make up for bad race results. I learned a long time ago that a bad racer on a fast bike is still a bad racer.
yeah, still like the idea of a simple, cheap & bomber steel privateer frame with a good bit of adjustability to keep it relevant for a handful or two of years.
that said, for reasons of longevity (and ultimately, good value) i'm a big fan of carbon as well. and there's the weight weenie thing, too...
despite this talk of CF full-suspension frames..and the expensive Devinci aluminium-alloy full-suspension mountain bike hanging on the wall next to me..
...for some odd reason I find myself drawn to the lure of my next frame being a hardtail made from Reynolds sublime 853 air-hardened heat treated steel?
and then you read about their 953 Maraging stainless steel, which has ultimate tensile strength of 1750-2050 MPa
imagine a full-suspension bike made from 953 with a Cane Creek damper, truly a bike for your lifetime
...for some odd reason I find myself drawn to the lure of my next frame being a hardtail made from Reynolds sublime 853 air-hardened heat treated steel?
and then you read about their 953 Maraging stainless steel, which has ultimate tensile strength of 1750-2050 MPa
imagine a full-suspension bike made from 953 with a Cane Creek damper, truly a bike for your lifetime
yes! which is why i continue to lust after the supertherm tubed superco silencer...imagine a full-suspension bike made from 953 with a Cane Creek damper, truly a bike for your lifetime
from what i've heard, 953 is VERY difficult to work with
it isn't hard to put some sheets over a mold and poor some rezzin and make it form.
it is hard to make that mold/form perfect and actually quality strong without air pockets for futur catastrophic failure.
many cycles of design revisions and FEA
Every material has benefits over another. Its also got negatives. As such, arguing that carbon has benefits over everything else is kind of pointless, as I can argue that Titanium has benefits over carbon, and styrofoam has benefits over that. Its the negatives that are a bit more important IMO.
This is not conspiracy either, its just a thread with an idea.
I also find comparing jets to bikes kind of silly. Yep, jets see far more stresses than a bike does. I have tried, but have yet to complete a 3g turn. Its tough. But I also know jets are really ****ty going through rock gardens, so its a trade off I guess. They are definitely faster in the straight sections though.
What I am questioning (so its clear) is not if carbon has benefits (which I already know). I am questioning if its really the best material for items that tend to go ass over ankles through rock gardens, smashing things along the way. I think this is questionable PARTICULARLY because manufacturers seem to be going for weight savings, rather than strength. Again, the only manufacturer that I've seen thats gone for strength over wieght was GT, at least publicly. Also again, not an "I love GT" comment, just the only example I can think of.
Yes carbon is the future it seems, but is it because its actually better or is it because thats what will sell so thats whats being pushed? Seems cyclists are forever searching for the holy grail that will make them faster, and they seem to think its the gear thats holding them back, ya know?
Again, just an idea. But cue forum grandstanding in 5...4....3...
This is not conspiracy either, its just a thread with an idea.
I also find comparing jets to bikes kind of silly. Yep, jets see far more stresses than a bike does. I have tried, but have yet to complete a 3g turn. Its tough. But I also know jets are really ****ty going through rock gardens, so its a trade off I guess. They are definitely faster in the straight sections though.
What I am questioning (so its clear) is not if carbon has benefits (which I already know). I am questioning if its really the best material for items that tend to go ass over ankles through rock gardens, smashing things along the way. I think this is questionable PARTICULARLY because manufacturers seem to be going for weight savings, rather than strength. Again, the only manufacturer that I've seen thats gone for strength over wieght was GT, at least publicly. Also again, not an "I love GT" comment, just the only example I can think of.
Yes carbon is the future it seems, but is it because its actually better or is it because thats what will sell so thats whats being pushed? Seems cyclists are forever searching for the holy grail that will make them faster, and they seem to think its the gear thats holding them back, ya know?
Again, just an idea. But cue forum grandstanding in 5...4....3...
We need to organise some sort of protest that this bike won't be released!
Pretty underwhelmed at this bike, was hoping to see a full carbon bike
I doubt I'll be buying a new DH bike anytime soon but I sure love drooling over new stuff. I reckon (hope) carbon will be the future for high end DH race rigs while there will be a lower spec Alu version for us mere mortals, think Spec Demo/Status.
Been on a carbon xc bike and after a couple hundred kms I think its pretty safe to say it rides like a dream.
Its not even that its much lighter but the stifness to hardness (huhuh he said stiffness) ratio is better then any alu bike Ive ridden including my Kona Kula, a titanium Liteville and a friends Yeti ARC.
I also did a DH run on a v10c on a day doing back to back DH runs on my alu v10 and was surprised how nice it felt.
Everyone who has their doubts on carbon is entitled to their opinion but its getting kind of old now that people are actually riding the hell out of their carbon bikes and loving them...
Its not even that its much lighter but the stifness to hardness (huhuh he said stiffness) ratio is better then any alu bike Ive ridden including my Kona Kula, a titanium Liteville and a friends Yeti ARC.
I also did a DH run on a v10c on a day doing back to back DH runs on my alu v10 and was surprised how nice it felt.
Everyone who has their doubts on carbon is entitled to their opinion but its getting kind of old now that people are actually riding the hell out of their carbon bikes and loving them...
Read what I read, and you'll see why your XC bike/ Road bike/ Off roadie bike has nothing to do with anything I wrote. I am saying purely for bikes that require testicular fortitude for riding.
Well carbon DH bikes have been around for a while and I havent seen to many people or pics of people smashing them on rocks and breaking them... And even if they would break on a rock, an alu bike would get dented and would be useless just the same.
Will it break faster then alu would dent? In some places where the carbon is thinner maybe, but its not like the current DH bikes have 0.05mm wall thickness.
I really havent met too many people who have dented a DH bike (except for the first sessions that were made of aluminum foil i think?) on a rock that bad that it had become
useless.
I wouldnt mind the small risk since I enjoy buying a new bike to go go faster.
All the BS aside, offcourse a rider makes the difference, but Im pretty sure that timed laps from one rider on, for example, a v10 from the first model up to the latest including suspension etc. would definitly make a difference...
Will it break faster then alu would dent? In some places where the carbon is thinner maybe, but its not like the current DH bikes have 0.05mm wall thickness.
I really havent met too many people who have dented a DH bike (except for the first sessions that were made of aluminum foil i think?) on a rock that bad that it had become
useless.
I wouldnt mind the small risk since I enjoy buying a new bike to go go faster.
All the BS aside, offcourse a rider makes the difference, but Im pretty sure that timed laps from one rider on, for example, a v10 from the first model up to the latest including suspension etc. would definitly make a difference...
You are misinformed.
Trek's OCLV bikes are all prepreg. Hodaka makes prepreg bikes for Kona, Evil, and others. Most high end carbon sporting goods, ie hockey sticks, handlebars, seatposts, baseball bats, golf club shafts are all prepreg. It is not some exclusive military, aerospace, F1 racing technology.
Understanding composites can be broken down into materials, resins, layup process, molds, compression of the layers, and curing of the resins.
Materials. Unidirectional carbon is the major type of composite materials used for highend sporting composites. This material provides the bulk of the strength of the part. By combining UD layers that run parallel to the tube, as well as at angles, you can tune the flexibility of the part. More layers add more stiffness and strength. You can get UD carbon with different thickness fibers, as well as different modulus.
Prepreg means that the carbon is preinfused with the resin compound at a certain percentage. You can get prepreg with more or less percent resin, as well as different resin that cure at different temperatures. The prepreg comes on rolls that are stored in refrigeration, and are heated up to temp to get the resin flowing, and then curing.
The idea is to bond the carbon strands together so that they form a grid structure. You want the fibers compacted together so there is no gaps between the fibers, and as little resin as needed. Gaps between layers and pools of resin add weight and decrease strength. You want heat to get resin flowing and curing, and pressure to get the composite layers to compress tightly together, and also to get the resin to flow out of the part, leaving the optimum amount of resin, full strength, with no extra. You control the resin flow by temp, and pressure.
Layup and molds. There are several different processes for making composites. You can do a male mold, where you wrap the composite around a mold, and then vacuum bag it to control pressure, and put in oven to control temp.
You can do female mold, where you have a clamshell mold that defines the outer shape of the part. You can wrap the composite around a machined foam core, that expands under heat at a given rate. Some of these foams are dissovable after curing. You can also use silicone inner molds that expand under heat. Or you can have an inner mold that you put a fancy plastic air bag over. Wrap the fiber around the mold with bag, then remove mold leaving bag, then attach an air chuck to the bladder to control pressure. This bladder method gives you the most control over resin flow and fiber compaction, because you can adjust the amount of PSI throughout the curing process as the resin warms, becomes liquid, and then solidifies.
http://www.vitalmtb.com/videos/features/Developing-the-Santa-Cruz-Carbon-V10-4,2365/sspomer,2
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^^
Thanks, great read.
Thanks, great read.
youd be correct
i stand corrected. really cool video, thanks for that.
I disagree and in fact that is one of the advantages of carbon - stronger AND lighter. SCB for one has touted the fact that their carbon frames are stronger and lighter based on their testing. I can't recall exactly but I remember something about the carbon nomad showing better numbers than an aluminum v10 in certain parameters.
In any case, you (and Sandwich) make good points and the whole thing is an interesting debate.
That video is really cool. I am surprised Trek showed off so much of their process. Most companies keep it more secret. I wish that Santa Cruz had more process videos. They do one piece front end, as opposed to Trek's lug process.
Bull carp fishies
BCD sure had a hard time....
If people want to rag on China, I guess that's there prerogative, but plenty of folks are able to kluge together adequately strong carbon frames from tiny Texan workshops with converted kitchen ovens to factories in China.
I guess I should expect this though as people still throw out the "Aerospace Aluminum" for 6061.....
We had this discussion before with examples here on RM and the high end stuff is actually cheaper. Only recently we have a new fashion of super expensive new stuff like bos rare, dorado carbon etc.
As for the why companies go with carbon now. Imho it is 2 things that are kinda connected. First is that FEA wasn't used in the biking community from the start. From what I remember it is quite new and doing carbon without it is a bit silly. People started designing bikes instead of guessing and made more and more carbon bikes for the low end disciplines. They gradually went up the "hardcore" scale from xc to dh just to be cautious. Not to mention DH is getting more and more popular now and am/enduro exploded so it makes sense to make more carbon bikes for dh and enduro than in the thinner years.
qft
and in the meanwhile wait for the evil undead i have no idea even though the reputation is shot it like that bike a lot...
BCD made some really cool bikes, but you can't compare his garage process to the processes used by Trek, Spec, Giant, Hodaka. BCD was doing wet lay up, foam core, vacuum bagging, in an old oven. Comparing that to a prepreg layup, female mold, with air bladder and auto clave, is like comparing a garage built 4130 bike, using a grinder and file for mitering, a MIG welder and a plywood jig, to a modern aluminum bike, with hydroformed tubes, precision mitering, tig welding, quality jigs, and heat-treating.
BCD made cool project bikes, but nowhere near the quality of high end production bikes these days.
Going end over end in a rock garden is going to be bad for pretty much any bike at a respectable weight, regardless of material. But strength under riding shouldn't be a concern as long as it's from a company that employs engineers and does FEA. More of a concern is in the little details, like how bearing races are integrated into the carbon, process considerations, QC and GD&T. That's that gravy you're speaking about! (inside joke).
Also, putting it your way, it gives people the option of super light race bikes (that DO stand up to riding as we watch on free caster), and more burly, averaged weight options Like the GT (which is on my short list). Win win really.
Also another picture that may not appear to relate to bikes.....
Hangar and upper house are carbon composites and has some ballistics resistance. Metal rocks. DDG1000.
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Rubbish. I rode that boat at Bromont and it cracked in a corner.
OH NOs! Carbons and steelz combined!
Awesome little article: http://dirt.mpora.com/news/homemade-bikes.html
Awesome little article: http://dirt.mpora.com/news/homemade-bikes.html