Bike manufacturers usually start with carbon composites in one of two forms prepreg or tubing. Carbon composite tubing is basically pre-cooked in a generic form that allows the manufacturer to cut the tube to size and glue it into lugs that can be made a variety of materials including: carbon composite, steel, titanium, and aluminum. http://www.yoeleowheels.com/carbon-cycling-wheels-clincher-38mm.htmlThis method of construction can provide more leeway as far as building with custom frame geometry. However, lugged carbon construction doesnt allow the builder nearly as much choice of tube shapes and sizes and doesnt allow a level of integration equal to a monocoque, which can result in extra weight and material and concentrates stress at the weakest points of the frame the bonded joints.

http://www.yoeleowheels.com/carbon-racing-wheels-track-tubular-38mm.htmlPrepreg, the other main way of using composites, is short for pre-impregnated, and it refers to a sheet of filaments pre-impregnated with uncured resin. The prepreg is adhered to tack sheets like the backing on shelving paper so that it can be more easily handled. Properly handled sheets are stored in freezers to keep the resin from curing prematurely, and in production the sheets are cut and laid up in climate controlled  rooms. http://www.yoeleowheels.com/carbon-wheels-cycling-track-tubular-88mm.html

To give bike frames their structural strength manufacturers employ a variety of unidirectional carbon fiber prepreg sheets. Each sheet is designated by the fiber orientation as being either a 0°, a plus 45°, a minus 45°, and/or a plus or minus  30°. Each orientation bestows a different mechanical attribute to the structure. 0° sheets build strength and stiffness along the length of the structure. Plus and minus 30° sheets resist twisting, and the 45°s fend off crushing loads. Together they determine the strength and stiffness of our little mechanical structure. http://www.yoeleowheels.com/track-bike-wheel-carbon-single-tubular-88mm.html

Another word youll here often when researching composite bicycle frames is. Monocoque - meaning a structure in which the shell bears most of the stress- composite frames are molded using layers of prepreg in a very specific sequence and orientation. In practical terms, this means that large components of the frame (like the front triangle) are formed as a single integral piece. http://www.yoeleowheels.com/cheap-bmx-rim-20-carbon-clincher-single-50mm.htmlIf properly designed and built, this unified structure distributes dynamic stress over a wider portion of the moncoque  The easiest way to avoid stress concentration at the joints is to not have joint at all . Monocoques also allow the Ibisians more creativity in the forms they can design. Which - on the whole - delivers you a lighter, stiffer, and more stylie (in our humble opinion) ride. http://www.yoeleowheels.com/16-bmx-rim-carbon-clincher-single-50mm.html

The sequence of prepreg layers is called the lay-up schedule, and is determined by a variety of methods. Lots of folks talk about how they employ FEA - finite element analysis - to develop their schedule, but what they dont tell you is that FEA is only as good as the person who sets up the analysis. And the more complex the form or the material, the more difficult it is for FEA to give you useful information. http://www.yoeleowheels.com/bmx-carbon-rim-20-clincher-single-38mm.htmlComposite materials and the interesting forms it allows are very complex. We use FEA to develop the basic lay-up schedule, but then the artistry comes in. Our engineers go to our factory to build up sample frames and test them over and over until they find just the right recipe that mixes the appropriate amounts of strength and stiffness at the lightest total weight.