Definition: "High Quality" or "Good" Carbon Fiber
#1
VFL For Life
Thread Starter
Join Date: Feb 2005
Location: Knoxville, TN
Posts: 51,228
Bikes: Velo Volmobile
Mentioned: 780 Post(s)
Tagged: 2 Thread(s)
Quoted: 28617 Post(s)
Liked 1,857 Times
in
1,319 Posts
Definition: "High Quality" or "Good" Carbon Fiber
In another thread a few posters commented on the expense of "high quality" or "good" carbon fiber. I'm wondering what the characteristics or qualities of these are, in contrast to "cheap" or "low quality" carbon fiber. And what's the difference in price?
While bike shopping earlier this year, I was under the impression that while the carbon fiber frames used by the major manufacturers (e.g., Trek, Specialized, Giant) may not equal the ride of a high-end bike, they are all of a fairly good quality. Is this correct?
While bike shopping earlier this year, I was under the impression that while the carbon fiber frames used by the major manufacturers (e.g., Trek, Specialized, Giant) may not equal the ride of a high-end bike, they are all of a fairly good quality. Is this correct?
#2
Senior Member
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Originally Posted by Velo Vol
In another thread a few posters commented on the expense of "high quality" or "good" carbon fiber. I'm wondering what the characteristics or qualities of these are, in contrast to "cheap" or "low quality" carbon fiber. And what's the difference in price?
While bike shopping earlier this year, I was under the impression that while the carbon fiber frames used by the major manufacturers (e.g., Trek, Specialized, Giant) may not equal the ride of a high-end bike, they are all of a fairly good quality. Is this correct?
While bike shopping earlier this year, I was under the impression that while the carbon fiber frames used by the major manufacturers (e.g., Trek, Specialized, Giant) may not equal the ride of a high-end bike, they are all of a fairly good quality. Is this correct?
#3
Senior Member
Join Date: Jun 2005
Posts: 132
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Design costs money: deciding how to orient the fibers, how thick to make each piece, etc.
Building also costs money. The more exact you need to be in your assembly process, the moe complex the assembly, the more expensive it gets.
I--or you--could build a CF bike in a weekend. With no experience. But it would be either 1) heavy as hell; or 2) wobbly as hell/unsafe to ride.
I have not seen the CF frames, though I see alot of CF in the boating I do. The main difference in taht realm at least is atht the higher end stuff has better manufacturiong processes, which either results in increased stiffness, decreased weight, or both.
Most intelligent builders will sacrifice a tiny bit of weight (hard to notice) for good stuffness (easy to notice, depending on application).
Of course, it's my personal opinion that a few grams don't maike a damn bit of difference at my level, so--were I to ride CF, which I don't--I'd be happy with a 'cheap' one.
Building also costs money. The more exact you need to be in your assembly process, the moe complex the assembly, the more expensive it gets.
I--or you--could build a CF bike in a weekend. With no experience. But it would be either 1) heavy as hell; or 2) wobbly as hell/unsafe to ride.
I have not seen the CF frames, though I see alot of CF in the boating I do. The main difference in taht realm at least is atht the higher end stuff has better manufacturiong processes, which either results in increased stiffness, decreased weight, or both.
Most intelligent builders will sacrifice a tiny bit of weight (hard to notice) for good stuffness (easy to notice, depending on application).
Of course, it's my personal opinion that a few grams don't maike a damn bit of difference at my level, so--were I to ride CF, which I don't--I'd be happy with a 'cheap' one.
#4
DEADBEEF
Join Date: Aug 2002
Location: Catching his breath alongside a road near Seattle, WA USA
Posts: 12,234
Bikes: 1999 K2 OzM, 2001 Aegis Aro Svelte
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 6 Times
in
4 Posts
While by no means complete and it's slightly outdated, I consider Craig Calfee's technical whitepaper to present a good read for the layman looking to understand carbon fibre bicycle frames. Some of the things I consider high quality about my particular CF bike include:
- High quality CF prepregs from reputable aerospace grade CF suppliers
- Manufacturing process that ensures high levels of consistant compaction
- Molded in fittings (water bottle cage mount inserts, cablestops/downtube shifter mounts, brake bolt inserts, etc) instead of rivetted or drilled so that the CF structure is formed around them
- Proper attention to isolation of dissimilar materials to prevent galvanic corrosion and if bonding is used to secure the inserts, they should be capable of handling dissimilar expansion rates
- Seamless non-clamshell layup and curing process so there's no weakness in the structure due to seams
- Attention to layers through creative and smart use of different bias and weave direction per layer to tune the mechanical properties of each section of the structure
- Reinforced layering at critical high-stress sections
- Use of a protective cosmetic final layer and finish
- Metal reinforced inserts as needed (headtube, BB, seattube)
__________________
1999 K2 OzM 2001 Aegis Aro Svelte
"Be liberal in what you accept, and conservative in what you send." -- Jon Postel, RFC1122
1999 K2 OzM 2001 Aegis Aro Svelte
"Be liberal in what you accept, and conservative in what you send." -- Jon Postel, RFC1122
#5
Senior Member
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Originally Posted by khuon
While by no means complete and it's slightly outdated, I consider Craig Calfee's technical whitepaper to present a good read for the layman looking to understand carbon fibre bicycle frames. Some of the things I consider high quality about my particular CF bike include: