Bandit 1200 idling issue.

[Flavrtwn]

Hi everyone, looking to get some advice on an issue I'm having. 

Recently my idle rpms have been fluctuating for some reason. I have adjusted it to around 1200 rpms while it was pretty hot but sometimes when I'm at a stop light it would either increase to 2k rpms until I feather the clutch or it would slowly decrease below 1k rpms and stay there while in neutral. Sometimes it'd idle properly at 1200. 

Any ideas what the cause is? Haven't messed with the carbs so any advice would be greatly appreciated, thanks !

Edited May 22 by Flavrtwn

[Gixer1460]

Immediate thought if nothing else has been changed or played with - Bad Gas ! Either contaminated with water or dirty and has clogged a jet!