Carbon Fibre

[bjohnson]

I'm putting my gixxer thou K5 on a diet and want some carbon fibre goodies.

I have a couple of questions which I hope the forum may be able to advise on;

- Firstly, is there a particular type of carbon fibre that I should be considering when looking at parts? There seem to be a variety of views on what is good and bad, what should i ideally be looking for, if anything?

- secondly, I'm after a few specialist parts that dont seem readily available. I'd particularly like a carbon sub frame and a carbon airbox to start with. Does anyone know where I might source these parts or if any companies will manufacture something to suit?

- Lastly, is DIY carbon worth considering??!! This one is a long shot, I'm pretty handy but certainly no carbon fibre expert!!

I did note a post on one of the readers specials on here from a bloke who makes his own. I've pm'd him but not had a reply.

Cheers

[originalracingsnake]

QB carbon are always a good place to start. Have a few bits of thiers on my K5.

[lorenzo]

For one off parts DIY carbon is not a bad idea, it's essentially like making fibreglass parts, in terms of getting moulds made etc, it's just harder to cut the cloth. In terms of structural stuff like self supporting subframes, I'd not chance it, but maybe that's just me.

[vfr4]

This is what Thorsten Durbahn has to say about weight savings, I'm not sure if there are negative consequences to lightening engine internals but the rest of it definitely makes huge amounts of sense. Its a C&P from the Durbahn USA site:

There's an order of Dignity of weight savings, means mods which should considered first ( Cat1 ), and which last ( Cat4 ) :

Cat 1: rotating unsprung mass ( i.E.: wheels /discs )

Cat 2 : rotating sprung mass ( i.E.: alternator /clutch)

Cat 3 : static but unsprung mass ( Brakes , Axles )

Cat 4: static and sprung Mass with sub-categories :

*

distance from center of gravity

*

volumetric weight + weight saving potential + possibility to get closer to this center

*

absolute height from ground

*

volumetric weight + weight saving potential + possibility to lower the height Components

+ All Components need to be considered regarding the Partition of weight which they have regarding the whole Bike and regarding the weight of all the Parts summed up in their category

+ All Components need to be considered in conjunction with the Money to spend for a mod

So some kind of Explanation here in example :

A real gain you get , if you locate the Battery ( which has a ~ 8 Times higher volumetric weight than gasoline ) somewhere near the center of gravity of the bike , instead of using the space for a bit more capacity of Fuel . So if you'd like a Factor of dignity in Category 1 , then the Battery has the highest one ....well, lets say 10 ,because :

- it has most volumetric weight

- it has most weight saving potential

- it is easy to move it somewhere nearer to the center of gravity

...........high end Battery's cost 230$ for 1600gr weight saving , that's a rate of 14 Cent per Gram

A Carbon front Fender compared :

Is in category 3 ,

- has no high volumetric weight

- has no real weight saving potential

- is not able to relocate

- has no substantial partition in category 3 ( a rear fender even needs to be considered from distance of pivot , so even less dignity )

.......a well done Carbon Fender cost 170 $ for 300 gr weight saving , that's a rate of 0,56 Cent per Gram

THE CONCLUSION : it is 400% better to spend the dough into a lighter Battery , than into a Carbon Fender.

.....just assuming you want to do something , which helps the Bike going faster .

And these 400% are only the weight-side , not even mentioned the opportunity , to move the Battery closer to the center , and nearer to the ground .

So , what I usually do to achieve a comparatively light Bike :

First of course : removal of all superfluous stuff , cost nothing / weight saving 100% , Quotient ( work not considered ) : infinite

In Category 1 I go for:

I : Magnesium wheels with superlight magnesium cush-drive

II : Max. light Brakediscs front

III : superlight rear Brakedisc, usually with reader-slots for Traction Control

In Category 2 :

I : ( Durbahn ) Race-Alternator , which has approx ~ 80 % reduced rotational Inertia or

I- : total Loss System with no Alternator, so purely running on A123 Cells with fast-charging inbetween.

II : Aluminum Clutchplates , which saved 66% of weight ( the OEM Clutchplates are steel )

III : if possible I build a much lighter Clutch, or at least I attempt to modify the clutch for less weight

In Category 3 :

I : a Rearbrake-Assy superlight , saves usually 2lbs

II : ISR or Brembo CNC Machined Calipers , which can save ~ 2 LBS

III :light Axles front and rear

Category 4 :

I : development of a light Fueltank , which is closer to the center of gravity .

II : development of a Carbon-Monocoque Tailsection , which substitutes the complete rear end of the Bikes ( saves usually ~12 to 13 lbs )

III : Use of latest Technology Batteries , weight savings up to 65 % ( so we're talking about Kilograms here.... ! )

IV : Titanium Exhausts , which usually save ~ 6 kg ( 13 lbs )

V : Rearsets I always build my own, which do not brake at a crash ( my buddy had 2 damaged swingarms from broken Gilles Rearsets )

VI : as light as possible wire harness ( more see Motec-ECU )

VI : the other usual stuff, as : Carbon Fairings , Carbon Air-runners , Carbon Fender