Have you tried the Google Translate app?
Point your phone camera at Chinese and you'll get something resembling English overlaid on the text on the image.
It's remarkably good, although sometimes you'll still be left with a puzzle; Chinese is a very different language, and idioms can be quite tough. But for basic instructions you should get something usable. Usable-ish, anyway.
For example, I get "Computer wheel balancer" and "Instructions for use" from that image of the cover, which seems pretty accurate. I set the language to "Chinese (Simplified)".
Try using Google Translate on the chapter titles to narrow down where the weight unit switching might be (assuming the machine can do this) and go from there.