Estarli e20

[AndyB78]

Hi guys. I’ve had an e20 for around 2 months now. Love it. Mostly for future reference, is it a freewheel or cassette? It seems unlike other bikes the power cable fits In the opposite side so no obvious obstacles to changing the sprockets but is there anything to be aware of? Must admit I’m keen to add some more range compared to the stock set up when I’ve worn the old cogs out with all the hills I have to ride up and down on my commute!!!