I have a Pro Rider E Tourer bike that's now about 2 years old. I have a problem with an excessive screeching noise from the rear brake when the brake is applied. It really is ear shattering! It also seems to be very "grabby" in the sense that it's now very easy to lock up the wheel with modest pressure on the break handle. The problem is compounded by the fact that the only wording on the brake assembly is in Chinese characters so I don't even know what kind of brake I'm dealing with.Can anyone help with some advice on what the problem might be and how to take the brake apart for repair/maintenance? A link to a YouTube video would also be appreciated as I can't seem to find one.