No magic formula to offer up except to check the usual...
Try fresh gas...
Crack open the float bowl screws and see if any crud comes out...
Try some SeaFoam or Techtron or Berrymans B-12 (my fav) in the tank...
Check all vacuum hoses for cracks, leaks, pinches, missing or loose connections...
Clean and or change air filter...
Good luck - let us know what you find... a few others are having downtime issues as well.