ORIGINAL: Nathan King

I purchased a used (but immaculate) Saito a few years ago and had a similar problem. Despite the engine being used it still hadn't been run enough to be fully broken in; a gallon later it could idle at 1900 RPM for a minute and still transition well without loading up afterwards. To this day it is the best running, most reliable engine I own. I also suggest you check valve clearances since most owners don't adjust them regularly (or ever). The Saito low end adjusts a bit differently than other four stroke brands as well; however, I find the Saito engines to have nice broad needle settings which are easy to set and will hold adjustments well.