Electric 29er electric hardtail bike electric mountain bike type mens wheel size 29 inch model 2016 series cube hybrid frame material aluminium frame geometry diamond bike frame sizes cm 43 53 48 58 cm bike frame sizes inch 19 21 23 17 inch engine model bosch performance line cx engine type bottom bracket motor motor activation pedal assisted assistance mode 4 support modes maximum supported speed 25 kmh without driving license and without ins