First time I fire mine up, I'm probably going to do so w/o the main blades installed to be sure I have my throttle setup properly. After it looks OK, I'll put the main blades on to provide the proper loading for engine break-in. Don't plan to run it long w/o the blades, just idle it a little and increase RPM enough to see when the clutch kicks in. After the blades are on, I've thought about tying a string to the carb fuel line so I can yank it if something goes haywire...