I have a 1500 watt xipi I love dearly. Did not use it over the summer, but topped up the battery once a month. Came to take it out and ride it and battery is completely dead. Could send it back to Frank, but it is £35 just to send it, and presumably £35 to get it back, and then repairs. I have a bit of engineering background and I am wondering if anyone on this forum could tell me how to go about finding out what is wrong with it, initially at least whether it is the computer in the battery or the cells itself. I certainly don't want to rip it open without guidance!