Sounds like you are exspecting the new Saito to run good right out of the box. Its going to take you better than a gallon of fuel on the ground to get that engine to run descent enough to fly it, and it will continue to break in and run better the more you fly it. Saitos are great engines, but they take a little time and effort on the breakin process. Make sure you follow your manuals breakin procedure if the engine is new. You should start to see your idle and high RPM get a little better with each tank. Even a good running Saito can shake things loose. I usually drop a little drop of thin CA on bolts threads to keep nuts from vibrating loose. You can still get the nuts to break loose when needed using the CA. It just makes them less likely to vibrate loose.