Having problems

[joneseyjnr200...]

Hey, i'm having problems with my 1991 gpz 500. Today on the way to work the revs kept dropping randomly, say from 6000 to 4000 then back to 6000, as though i was shutting the throttle then opening it, jerking me about, also at slow speeds, and when moving off, i had to give it alot of revs to stop it cutting out.

I live 5 minutes away from work so i thought i'd chance it back to my house. Same story on the way back, but it backfired this time, which its never done since i owned it.

Anybody any ideas what this could be? I'm fairly new to bikes and no mechanic, but i'm willing to sort this myself if i can.

Comments much appreciated guys, cheers.