I have a Honda genset here that my father bought second hand in 1990 when he was building his new house.My son, he is a electrician, said back then that there was something wrong with it because it wouldn't do something, can't remember what the problem was. It has sat around since then and I started it about 18 months ago and it was strong enough to start two 9 inch grinders at once, so it hasn't lost its magnetism obviously.