I also notice, well my o.s. 50 seems to be running at higher RPM's, I don' think this would need to be carried to an airplane though, it is just capible of running high RPM's. But it will just stay cooler, and yes, they need to be ericher, my helis are very rich, or they won't run, I think they can be leaned out when you get a prop on it to cool it.