Jiu Yu might not be a well-known name in the West, but they're working hard to gain attention. Their reputation may not be widespread, but there's a way to recognize their work; if your bicycle has an OE mark, it was likely produced in their factory, as Jiu Yu is the world's largest supplier of bicycle hubs. Recently, we had the opportunity to tour their factory in Taichung, Taiwan, to explore how a product is made step-by-step.

　　A factory can't change its production methods just for our visit, so this article provides the production processes for several different types of workshops. These products are indeed produced in the same machines, in the same way, only the technology and material quality change according to the needs of the product being manufactured.

　　This is the beginning of product production—starting with aluminum rods. A CNC machine's computer system has a very strict standard for aluminum rod production (I find it difficult to fully translate this Chinese name). Different machine settings can produce aluminum rods of different specifications, but this is the key to the start of production. The rods are then cut into sections, ready for cold forging.

　　The cold forging workshop looks a bit like hell. The day we visited, the cold forging control room was under repair, so we couldn't see inside. Apparently, the metal is shaped by being extremely compressed in a mold. But to deform the metal requires immense force, and this machine provides 500 tons of force—it's hard to imagine such immense power, a force that certainly no human body could withstand.

　　Parts undergo heat treatment. Simply put, the metal is like being cooked, and the 'cooked' metal becomes harder and less prone to deformation. When compressed, it's more likely to break than deform easily. This also means it's no longer easily reshaped. It will retain its shape, and of course, you wouldn't want your hub to deform easily.

　　The basic shape of the hub is created through forging, and forging must ensure very small tolerances. The next step is polishing and CNC machining of the parts.

　　Comparison of hubs before and after polishing. You can see the difference between the refined appearance of the polished part and the oxidized shell formed on the part before polishing due to heating. Like many factories, Jiu Yu outsources the polishing and deoxidation process to another company elsewhere.

　　Once the polished and deoxidized hubs are returned, Jiu Yu's workers begin the painstaking and precise process of applying the Jiu Yu logo to the hubs.

　　Finally, these hubs are sent upstairs for assembly. It's surprising how many steps and parts are needed to assemble a single hub, and it's all done by hand. First, the bearings are precisely pressed together using a hydraulic machine.

　　The process of assembling the hub is incredibly complex, and it's amazing how many tiny parts need to be put together.

　　When the hub is assembled, at least two more steps are needed to complete the process, and all the parts need to be tightened.

　　This is the most impressive step of the whole process. Workers are trained to identify faulty hubs by sound; they can pick out problematic hubs from a pile by listening to the sound they make when rotated. This process requires several different workers to repeatedly inspect the hubs to ensure that those with quality issues don't leave the factory.

　　Finally, you see a refined hub.

　　Not all hubs are shipped immediately after production; some are sent upstairs where workers manually install them onto wheels. These workers assemble at least one hundred wheels a day and observe the precision of the hub's operation at high speeds—it's all quite amazing.