Really some great advice from all the bench guys. I have a bench set up that allows me to set the tank height and distance to match the plane. Break the engine in and tune it, then put it in the model. Glad to hear the non-benchers have great angels watching over them, but most of the time I try to tune the new engine at the field has robbed me of good flying weather and even cost me an airplane or two. I recently bought a brand new FX.91, which had bad bearing right out of the box, had to send it in to Hobby Services under warranty. This kind of represents this Irishman's luck. No body has problems with new OS's, right? when I finally get the new engine back, you can bet it goes on the bench to be set and tested, before it goes back onto the new UCD60. Most manufactures recommend running the engine on the airplane, but I am old and hate bending over for adjustments and so on. My neighbors ride Harleys so my little ole engines don't even come close to their straight pipes. Nearly every member of my three clubs has a good bench and uses it regularly.