the issue with it pulling real hard to the right could be unevenly inflated rear tires, worn/sloppy axle bearings, worn/sloppy swingarm bearings or any combination of the 3. as to the hanging idle on decel, along with checking the reed petals as suggested, check the carb boot for cracks and weatherchecking. if there is any air getting sucked in between the carb and reedcage, it will lean you out and can cause what you are describing