I've been driving 2 types of electrical scooters for the past years, mainly in the summer months, it's the best way to get around here in Shanghai
The one I use now is 800W, 48V and I've been driving it for 2 years. It runs 50 km/u and that's with standard specs. It's one of those Vespa looking e-bikes..
Lots of people here in Shanghai try to make these scooters run a bit faster.. My friend took a standard electric scooter, 48V, 800W, and made it run about 65km/u by 2 simple adjustments:
1. Add another battery in series, from 48V to 60V
2. New controller. It runs 70km/u+ and it works well for over a year now.
A technician at an e-bike shop here told me even 70V works fine with these 800W electric motors. It seems the controllers get larger in size, the higher the voltage, and are usually mounted on the outside of the scooter (not enough space). Also he told me he can replace the 800W motor to a max. 2000W size, for those who are really suicidal
In my opinion making these e-bikes run faster is fun, but I noticed my 4x 12V batteries have started to degrade after 2 years of usage.. If you demand more from the batteries I'd give them a 1-2 year lifetime or so..
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