There is very little difference between the Xiaomi M365 and the newer Xiaomi 1S: the 1S is simply an upgraded M365. Indeed, the 1S should really be called an M365 Mark II or M366 or some such. But this guide will give you some extra details to help you choose between the two Xiaomi scooters – but the only reason you would buy an M365 is if it is offered at a lower price.
The main difference between the M365 and 1S is that the 1S has a speedometer as well as a battery indicator on the display (below, right) whereas the Xiaomi M365 only has a battery indicator (the four LED lights). However, there is a speedometer within the Xiaomi Mi phone app, meaning you could attach your phone to the handlebar and get your current speed from that. The 1S’s display is taken from the M365 Pro and, likewise, the 1S has an extra mode (beyond normal and economy mode): sports mode.
After the display (and sports mode), the main difference is the battery. The 1S does not have a more powerful battery (meaning it is not faster), and its battery does not carry more volts (it does not last longer), but the battery in the 1S is said to be more efficient so as to allow for a faster charge time and increased overall lifespan. The Xiaomi M365 has an advertised charge time of 5.5 hours, while the Xiaomi 1S has an advertised charge time of 5 hours.
The only other apparent difference is the brake on the 1S is the same as the brake on the M365 Pro, meaning the disk pad is slightly thicker.
This is an edited version of this post comparing the Xiaomi M365 and Xiaom 1S