I was wrong I guess they do come pre run, Novarossi Direct doesn't offer them yet but Absolute Hobbies has some. I would run at least 2 tanks of whatever fuel you plan on running at idle through it, then put it on the track at no more than 1/4 throttle for a tank, 1/2 throttle next tank, 3/4 throttle tank 6, last tank at full throttle. I have heard pre runs are suppose to be from the box to the track readt, but If it were my engine I would take I slow. You wont hurt anything by taking east for the first 4 to 6 tanks