I have a 93 bayou 300 that was blowing the main fuse after riding for a while. I would change the fuse and it would be right back in action. last time I rode it the bike shut off as it always would. I changed the fuse now the plug wont fire. any ideas on where to start?

 

blowing fuse was a warning sign. You should have checked the amount of charging coming fom the charging system when unit was running. Unit probably has a bad regulator/rectifier which allowed the unit to over charge and blow fuse. The unit finally got your CDI (brain box) now you will probably need CDI Regulator/Rectifier and new fuse. First thing I would do is to check to see if you have power at the ing switch when replacing with new fuse. If you do then trace the wiring harness after removing the racks and body, for any crispy, chaffed,or noticably burnt areas. If nothing apears to be wrong with the wiring I would suggest the above happened. Sorry to say it's gonna be very expensive.
Hope this helps,
Jody