The DYU R1 e-bike is a compact, comfort-oriented city bike Naomi Wu test-rode around Shenzhen: about $800, 20 kg aluminum frame, 20" tires, removable battery and 250 W hub motor with one gear and three pedal-assist levels. The manual includes electronics schematics and torque specs; it supports up to 150 kg but needs rider help on >15° hills and is not foldable or cargo-capable.