yamaha Neos 50?

Hi everynoe. I have a yamaha neos 50. Standing around for a bit. battery was duff and so i replaced it. When I put new one on I had the ignition on, I didnt notice and the fuse blew and there was a flash. So I replaced the fuse. I now cant get a spark for love nor money. I had a spark before. I have replaced plug, coil leads from a working bike. Now I am at a bit of a loss. I have to admit my bike knowledge ends at the HT lead... I have been told possible CDI or condensers? Where would I find these? Or am I baking up from tree? I will be very grateful for any advise as my bike is a work bike and I need it really.