http://chinertown.com/index.php/topic,5263.0.html
It's easy, ask questions. Honest sellers answer them. You're also less likely to be shipped a shitty frame if the seller perceives you as someone who is more likely than average to notice problems. When you sell things to people who have zero understanding of what they're buying, especially with his Chinese culture is, it's very tempting to meet quality fade. Asking questions is a good quality fade hedge.
another clue can be the weight, no doubt that EPS molding save the weight (one big layer is better than several small layers), more than 100gr for sure
but if i compare to western compagnies , i have some questions.
For example canyon is famous to build the thinnest (and fragilest) frames (the process is pretty optimized), the ultimate frame is given for 1050gr(cf), 850gr(slx), 730gr(cfr). if we ignore the CFR which use expensive HM M... carbon fiber, i wonder how can OEM chinese factories reach these weights with thicker frames (even by using EPS molding). Giant TCR is around 850 gr too, maybe helped by the slopy frame.
With my short knowledges, i understand the following facts:
high modulus means same stifness than low modulus with less material, less weight but fragiler due to a smaller tensile strength
T800 and T1000 show the same stifness but T1000 is 10/15% more robust and 10% denser
T700 is 20% less stiff than T800/1000 too but slightly more robust than HM carbon fiber (starting by M..)
T800 is at least 30% more expensive than T700
So how can chinese OEM factories produce the same weight than a slx with ticker frames, with probably the same fibers (not the same supliers or/and coating), and with a less controlled distribution of fibers? i use to say to an friend who is astronomer: dark matter takes place within chinese carbon frames but weight is missing.