Most people don't know how the fairings they are going to buy will fit, unless they ask someone who has that brand already. Reason #1 why aftermarket fairings that are fiberglass or carbon fiber don't fit right... simple answer, the mold was made wrong. Every part requires a mold to be made. Molds can be made of several different types of materials; metal and FRP are the most common. Metal molds are super costly to make so you won't find those in hardly any manufacturers shop. A Metal mold can cost as much as $8,000 depending on how much work is required to make it. Corvette molds are aluminum metal. FRP molds is just an acronym for Fiberglass Reinforced Plastic. These are the molds that all bike fairing mfg's have and use.

Now break that down even farther. There are two kinds of FRP molds; epoxy, and polyester resin. Each are reinforced with mainly fiberglass cloth or mat, kevlar, or carbon fiber. It is VERY time consuming and difficult to make these molds and get them perfect. Polyester molds suck, they can shrink during curing as much as 5-7% overall. See now you know why your cheap *** aftermarket fairings don't fit right and dont' line up. Epoxy molds will only shrink about 2% overall. I prefer epoxy when making my molds. There are "secret" ingredients i use in my mold making epoxy that give it the properties i need. This shrinking occures from the curring process and cannot be avoided. It can be minimized somewhat by the way the mold is made and time. Why don't all manufacturers use epoxy molds... simple it's more expensive and time consuming, requires more skill from the person making the mold.

Reinforcements:

These are the cloth or mat materials used to make up the part. These include fiberglass mat, fiberglass cloth, kevlar cloth, or carbon fiber cloth. It is possible to "intermix" these reinforcements in the resin matrix. Most cheap aftermarket fiberglass fairings are made out of mat and polyester resin... why.. because it's fast and cheapest. Move up the ladder one notch and the manufacturer will use only fiberglass cloth to make the part and no mat. This makes for a stronger, lighter part. Remember... mat fiberglass parts suck a*s. They are heavy and brittle when compared to cloth made parts.

Carbon fiber and kevlar fairings are the strongest and lightest you can buy. Carbon Fiber weighs about the same as fiberglass cloth does, but it's WAY stronger. Kevlar is used to help hold the composite part together in the event of a crash, it can also be used to strengthen tabs and mounts in the part.

RESINS:

There are three types: Epoxy, Polyester, and Vinylester. Polyester is the cheapest, weakest and most brittle of the three. Do expect most fiberglass fairings to be made with polyester resin. If the manufacturer doesn't say what they use..it's because they are using polyester and they don't want you to know.

Vinylester is better than polyester and most times it has a UV inhibitor in it but for fairings that use a gel coat surface that doesn't matter much. Still it is a higher quality resin and costs more than polyester resin. I believe VinylEster will flex more than polyester resin will without spidercracking.

Epoxy is the superior resin of the three types. Epoxy isn't UV stable so it will turn a yellowish golden color if not clearcoated. The sun causes this for the most part. But good parts made with epoxy are either painted or clearcoated and that will protect them from the sun's rays. All my parts are made using epoxy resin. There are hundreds of companies and types of epoxy resins. Each has a different property... this is usually a trade secret with carbon fiber parts manufacturers. The epoxy i use is clear and re

 

very informative...thanks for the heads up....this type of information is great to know even if you don't plan to do it yourself...i would love to see samples of the different types....not that this isn't great by itself....

 

[sm=ttiwwp.gif]

 

Pretty over simplified IMHO, But I have a degree in composite engineering...
But you leftout a few important things like:
Layup quality and overlap of layering
Amount of resins used
Intermixedtypes of fabric
Dry fabric vs pre-preg
Thread counts
Types of curing - Air-cure, UV cure,Autoclave

I'll also disagree about Epoxy resin being superior to Vinylester resin when used with fiberglass bodywork. In my expericence Vinylester resin is superior to Epoxy resinwhen used with fiberglass becuase if it's flexability. This allows the bodywork to flex and bend rather than craking and breaking during a easy crash.

Also having had alot of first hand expericence with many different types of an bodywork (Buying, repairing and even making my own)from the cheapo stuff to the uber expensive, I'll make a correction:

Fairing set, fiberglass for under $500: Most use low thread countcloth and polyester resin, sloppy lay-up, miniminalnumber of layers. I have never see race glass made from mat, fenders yes but not main bodywork or tails.
Fairing set, fiberglass for over $500:Most uses low - mid thread count fiberglass cloth and polyester or vinylester resin, good qualiy lay-up, good thickness.
Fairing set, fiberglass over $900: Most use mid - high thread count fiberglass cloth and Vinylerter resin (there's a few using epoxy resin, but not many), excellent layup, and good thickness (but a few are too thick). Also most bodies in this range have kevlar or carbon/kevlar layed into it duringthe layupat the mounting points.

Fairing set carbon fiber under $1200: Not 100% carbon fiber (Fiberglass with a couple layers of carbon over the top) or very few layers of carbon, Vinylester resin or Epoxy resin.
Fairing set carbon fiber over $1200: Kevlar and carbon fiber with Vinylester resin or epoxy resin, Lay-up and curingis usually pre-preg and autoclaved.