I'm of the exact same opinion as ckangaroo70 . I've had two tower .46's, the first one died a premature death when the entire piston cracked down the side. It hadn't completely come apart, but it wouldn't run reliably so I tore it apart and found the crack. Tower replaced it, although they were nice enough to include a note saying although it wasn't due to a manufacturing defect or anything under their control, they were still fixing it. (this engine had maybe 3 runs on it, was still being broke in)

anyway, engine #2 was a horrible @#)(*% to tune. It would seem like once you had it tuned, it would hold it for a couple minutes if even, and then you start from the beginning. (the needles were NOT moving on their own either due to vibration) overall one of the worst engines I've had.