So if a carbon frame weighs the same as a steel frame the carbon one will be stronger?
Do carbon frames weigh the same as steel frames?
@ Frank, the other week the guy fro Top gear was doing a feature on Carbon / Kevlar and went to a company that made drive shafts for F1. They put it ian a machine to torque it / make it twist. Steel started twisting at 1500 ft /lb and the carbon went over 4000 for memory before twisting.
It was the one he does thats shown on SBS, not sure on name
The problem with carbon fibre is not its strength, as such, but its failure mode, which is always catastrophic. The fibres, if overstressed, dont give a little, they just break. There is also very little defect tolerance. (Unlike steel.)
I wonder that there are not bikes around made using aramid fibre ("Kevlar"). This material, although somewhat heavier than carbon, has a very "safe" failure mode, and is somewhat defect tolerant.
Some cheaper "carbon" frames do include kevlar to keep cost down, at the expense of stiffness and weight.
actually some very expensive carbon frames have kevlar in them too. I have never seen it in a cheap frame (they use fibreglass fibres). TIME use some kevlar in their carbon fork steerer tubes - an obvious place where catastrophic failure really is catastrophic. Makes them a lot harder to cut for a start!
kevlar would make an interesting material for bicycle security, with it's reluctance to being cut, and quickly blunting anything that tries to cut it.
Kevlar is good for tensile force applied like stretching but not compression plus is no good when exposed to UV and its known to absorb moisture.
Great for body armour, plane bodies that tend to twist and deform etc.
Time make the best bikes in the world imho. (Just cause I have one), pity they are french and so frickin arrogant.
catastrophic like this.....