on the frame behind the carbs,little plastic thing in the tank vent hose clipped to the down tube. Also if the filter was dirty you may need to clean the petcock too if you still have a problem.. Doesn't take much to clog that little hidden filter so you may have found the issue.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!