Hi,

I now have an almost mint condition MV Agusta F4 750 SR in my garage ... yeahhh ...

Of course it will need a complete CF "workover" starting with all the little bits, and ending up with making a full set of CF fairings.

Now to the Q ... I'm going to build most of it using infusion, and most parts will be painted, so surface quality is not such a big concern..

How many layers of which CF fibre (I plan on at least one layer of Twaron for impact resistance on some parts) will be the best compromise between strenght and weight?

Since I'm not building this to make money, but to improve on my own bike, economy is not the biggest concern ...

I have a large stock (20 m +) of  "Satin Weave" CF 375 gsm ... So I plan to use that for most of the parts.

Any advice will be much appreciated :-)

"Sapere Aude"... Dare to KNOW!

The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind...

103% of all people do not understand statistics...

Do not adjust our mind, theres a fault in reality :-)

As a very minimum i would be looking in the 0.75 - 1mm thickness if using full carbon.  However you may get stiffer results using less carbon but a foam core so the panel could be quite thick but mostly just be foam.  A super light skin might be a single layer of fabric either side of a 2 or 3mm Soric core or even PVC foam core if its not too curvy.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

I use two layers of 200 gram fabric and infusion plus two extra layers on stress/mounting points, however this is for a race bike that req min weight but I would use Warrens suggestion for a road bike.

Chris Alty

www.carbonfibreworks.co.uk

Thx Warren & "Barton"

The seat part is already CF, looks like hand lay up cross-weave, about 1 mm in thickness.. It seems to ba a factory part, and has stickers on the underside from the factory. It must have been made in a multi part mold.

It is very stiff and seems to be very strong..   funny to see that you can actually just make out the weave pattern under the red paintjob, as a gentle ripple in the paint.

I think I will go for a 4 layer approach:

outside layer 2/2 twill, Pro-finish in the visible areas, then Twaron, then 2 mm Soric in larger flat areas, and 375 Satin weave on the inside ... does that sound like a usable approach??

This will probably be much stronger and stiffer than the factory ABS parts, which seem to be rather flimsy and "wobbly" when off the bike...

Later I will look at the more complex parts ... Airbox ... Ram-air tubes ...e.t.c.  That will be real fun ...

"Sapere Aude"... Dare to KNOW!

The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind...

103% of all people do not understand statistics...

Do not adjust our mind, theres a fault in reality :-)

Hi Dravis

The pro finish does not like compound curves so do a small test piece first, nice bike the MV F4

I've made stuff like this with 2x200g layers.  Make sure you put the second layer at 45 degrees to the first, it makes quite a difference!  Then use a 3mm foam core followed by another 2x200g.  The core will bend quite a bit if you heat it but don't go too mad on the shapes.  On bolt holes either add a couple of layers of 600g or an aluminium washer. 

If you need to use profinish I found that acetone seems to affect the binder meaning it will go into minor compound curves.  It seems to dissolve the binder which re-sets when the solvent evaporates. 

Check out www.compositescentral.com

Here is a front mudguard I made earlier, it has had the excess carbon removed and has yet to be polished. I used infusion and three layers of 200g carbon and a strip of core material to reduce torsional flex.

Looks good!!

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Nice Barton !