Re: losing power at high rpm
too large of a gap could make it 4 stroke. i run mine at .025
bad fuel or water in it could hurt it, too.
you say you've changed the plug wire, is it on there tight? mine has a "snap" to it when it's on all the way. once, i didn't snap it on all the way, and it four stroked at high rpm.
double check that all your wiring connections are tight.
it might actually be too lean. it's easy enough to go down a notch to see if that helps.
what kind of oil are you using, and what mixture?