jsallade - I hear what you're saying, but if DLE says the max HP for the DLE 20 is 2.5HP at 9,000rpm, I took it to mean that 9,000 is the RPM where this plane will produce it's greatest power. Now that I look closer, the specs do not say which prop was used for that test. Also, does that mean that anything over 9,000 will not produce extra power? Or, if you go smaller diameter \ higher pitch prop you are then trading thrust for speed, i.e., the prop (your transmission) is in a higher "gear'? If that's so, just wondering if mfgs should also include a "max recommended RPM" number. Or maybe that would be asking for trouble, warrantee-wise. Just wondering now how many RPM's these DLE's can turn before they start to tear themselves apart or wear out prematurely. (not that I'm looking to do that - I"m happy with my 16x8 for now).