For a few remarks, E300 first eight years and only ran about three minutes per charge and a top speed of 13 kilometers per hour (yes, I have the radar gun). Trouble Shooting sent us on the brakes pull, but brake adjustment was good. Chain, but it was difficult to cool (I have an old bike, so I do not know much voltage). And apparently the tension of the chain, but has not improved, and sent the whole group. (I suspect a bad battery or too short a chain of structures damaged