Chain rings: 39T outer 26T inner. Bottom bracket type: GXP. Abrasions on surface of drive side crank arm. Abrasion on outside surface of non drive side crane arm. Abrasions on ends of crank arms. Wear on teeth.
Bafang Model: M315 MM G340.500. A: This 68mm mid-drive motor is compatible with bikes having a bottom bracket width of 68-73mm. For 73mm bottom brackets, we'll provide extra installation accessories.