RE: Is it a phenomenon of these little 2-strokes that until well broken in, they will not turn a larger
Just for the record, some of the older .15s will run quite happily on a 9x4. But I wouldn't bother using one on a modern Magnum 15.
Peter Chinn found the old Enya .09 III would run very well on a TF 10x3.5 without overheating. Obviously most engines aren't designed to do that.
Jim