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Discussion Starter · #1 ·
Hey there guys,
I was wondering how a significant a reduction in weight one can get from carbon fiber and what is the compromise on strength. Also, which carbon fiber parts replace original parts and which ones are add-ons?
 

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Hey there guys,
I was wondering how a significant a reduction in weight one can get from carbon fiber and what is the compromise on strength. Also, which carbon fiber parts replace original parts and which ones are add-ons?

It depends on what you want.
Hard parts like fuel tanks, swingarms, frames, subframes and wheels still have metal cores to allow mounting and attachment - usually aluminium or magnesium but the weight savings are still significant. The cost though is huge per kg saved so I wouldn't be spending the money on CF if you've still got things like a toolkit or pillion pegs hanging off your bike :)
The non-load-bearing stuff like engine covers and fairings are much cheaper but also the weight saving is less significant than with fibreglass. A good fibreglass fairing kit should be around one-third of the weight of your OEM plastics for well under US$1000, CF might be closer to half of the OEM weight but at much higher cost. With fibreglass fairings you might drop 4-5kg off your bike, CF might perhaps drop 6kg of weight.
An aluminium or carbon/fibreglass fuel tank is a significant weight saving because it's so high, but aluminium is more crashable.
 

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Discussion Starter · #4 ·
And what is the deal with ABS plastic? Is carbon fiber the lightest option? Can you tell me some decent manufacturers?
 

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And what is the deal with ABS plastic? Is carbon fiber the lightest option? Can you tell me some decent manufacturers?

All the plastics would be similar weights.
Carbon is the lightest I'm aware of.

Did you try Google?
Google
 

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what about kevlar?
As far as I'm aware Kevlar is only used as a reinforcement in panels of fibreglass or carbon. I'm not aware of anybody making Kevlar panels.
 

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For reference, carbon fibre in solid form (rod) is roughly half the weight of aluminium - about 1.4gm/cc.
Steel is around 8gm/cc.
Titanium is 60% of the weight of steel - 4.5gm/cc.
Aluminium is one-third the weight of steel - 2.7gm/cc.
Magnesium is almost half the weight of aluminium - 1.75gm/cc.
Fibreglass is roughly the same weight as magnesium.
ABS is around 1.1gm/cc.
 

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Discussion Starter · #9 ·
So ABS is the LIGHTEST??? We don't get fairings in any of the metals do we? Can you tell me the best websites and manufacturers for fairings and bodywork?
 

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So ABS is the LIGHTEST??? We don't get fairings in any of the metals do we? Can you tell me the best websites and manufacturers for fairings and bodywork?

ABS is light but it has little strength so you need much more of it.
It has no weave through it like fibreglass and carbon fibre which is where their strengths come from. Carbon cloth is only 0.25mm (0.01") thick.
Polystyrene foam would be even lighter but has no strength at all :)
In the fifties and sixties race bikes were running aluminium fairings which would quite possibly be lighter than modern ABS fairings but nowadays I'm not aware of anybody doing metal fairings except for Historic racing.
My personal preference is our locally made Race Glass as it's amazingly flexible with an excellent finish.
In the US I couldn't say as I haven't seen or used any of them but Shark Skinz is one that comes to mind. Just Google as there are hundreds of manufacturers.
Or you can make your own of course.
 

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Discussion Starter · #11 ·
So what would the overall weight comparison of fibre glass to carbon fiber to ABS be like to a full fairing set? Is ABS durable..does it measure up to the other materials in terms of strength if it is used in a greater thickness?
 

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So what would the overall weight comparison of fibre glass to carbon fiber to ABS be like to a full fairing set? Is ABS durable..does it measure up to the other materials in terms of strength if it is used in a greater thickness?
As I said earlier, you would expect a good racing fibreglass kit to be around two-thirds of the weight of the OEM plastics but it depends on how they're made. Fibreglass is probably half thickness of OEM plastics.
Carbon is pretty tough but I doubt anybody would make fairings just one ply thick. I haven't seen many CF panels but those I have seen are noticeably thinner than fibreglass. Good CF you might perhaps get down to half the weight of the original plastics.
 

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A good fibreglass fairing kit should be around one-third of the weight of your OEM plastics...
Just spotted a typo:
It should be _two-thirds_ of the weight of the OEM plastics.
 

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Discussion Starter · #14 ·
do you know anything about pro series available on oppracing.com? because they have full carbon fiber fairings which are available nowhere else...and why is it that motogp teams use fibre glass when carbon fiber is lighter and almost as strong...what am i missing here?:idunno:
 

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do you know anything about pro series available on oppracing.com? because they have full carbon fiber fairings which are available nowhere else...and why is it that motogp teams use fibre glass when carbon fiber is lighter and almost as strong...what am i missing here?:idunno:

No, I'm not familiar with those specifically but there are other people doing full carbon kits.
I doubt MotoGP teams use fibreglass but it's possible they might for some specific reason. Some teams run carbon swingarms and rear subframes as well.
Carbon is far stronger than fibreglass.
 

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:eek:It is? It's done then...how much does reinforcing CF with kevlar increase its weight by?
The glass-reinforced plastics are all fairly similar in weight so it just comes down to thickness. If you add the same thickness over 20% of the panel then it'll be 20% heavier than it was without it. If you have a carbon fairing 1mm thick and you add 1mm of kevlar then you've effectively doubled the weight of that section of the panel.
If weight is your reason for going with carbon then I would recommend having the manufacturer confirm what their panels weigh before you buy them.
 
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