i have a PA50II w/ 2-stage reeds, proma pipe, 80 jet, notched vario w/ 9.6g weights. it used to go upwards to 40. now it goes just a little over 30. i thought i had an air leak, but apparently, i do not (took off, sealed, checked).
the bike runs fine. vario is opening fully. it's just not the same ol' bike. goes slower. plug chop is good and clean.
things it is not: stuck brake, clogged pipe.