Mao would be turning over in his grave?
He's spinning high RPM. Had 'The Mummy' film franchise not already done China, the old Commie would make the perfect resurrected villain!
'Flying Pigeon' is a great story about how privatization can work. While many privatized state companies just died because they were totally disconnected from the consumer, the woman that owns FPR
forced that connection on the company and the rest is amazing history. There was a Wall Street Journal article on her about a year ago.
I think for tech info about parts, you're going to have to connect directly to Shimano, SRAM, Campagnolo, etc. The reason that there's no technical info on the web is that they don't release any. weightweenies, for instance, has taken 'weighty' matters into their own hand. But their info trails the market somewhat. Shimano does offer some not-all-that-realistic compatibility data on their own products, but not in digital form.
IMO, though, you have a deeper question to answer: WHY. And once that is answered, extrapolate to define the audience. It won't be manufacturers. It will be people with existing bikes needing to replace or upgrade. For the larger manufacturers there
is no aftermarket, just OEMs and customers that need replacement parts, supposedly service by their dealers (LBS). If you can show them that there is a potential direct aftermarket that is limited primarily by lack if info, maybe you can pry some data out of them.