heres the situation.. bought my bike, the electrics were never too good.. the headlight would dim when the brake light was on.. and it got worse and worse until the bike wouldnt start one morning..
i bump started it and it was fine for a bit.. but if i left the headlight on for more than 10 seconds it wouldnt start again..

i replaced the battery thinkin this would sort it out and it did for a month.. until i smelt the battery one day and i saw that it was boiling hot! so i disconnected it and left it.. someone said it could be the rectifier.. looked at that and there was a massive crack in the back of it..

replaced the rectifier and it sorted it it out for another short while until it got too hot again one day and that battery actually blew up

whats causing the rectifier to go? cos i tested it when i first got it and it must have been working fine.. cos the voltage on the battery when the bike was running and revved was reading normal :/

All sorts, the chasrging system is generally not great.

Start by looking at the plugs all along the system, one with 3 yellow wires each side, and the one going into the rectifier. Read off the voltages and tell us what it's doing.