What kind of shape is the suspension in? When was the last time the forks were serviced? Lugging it may very well be the case, but proper suspension set up (setting the sag, and making sure everything is in good working order) makes a huge difference.
"Just stay in the fast lane, and keep moving, you cannot predict your final day, so go hard for the good times while you can." Kenny Stabler
'08 DRZ 400sm - FCR, E cams, SSW / MRD, Tuned by Wheeler
'02 XR 50 - 1/4 scale stunt bike