89 kdx farting until high rpms

[bill kdx nj]

fmf pipes
ported polished fredette
1173 needle middle clip
48 pilot
air screw 1 360 turn out
#6 carb slide
152 main

it has a lugging sluggish feel until i reach peak rpm when it hits sweet; when the fmf pipes make their sweet sound.

how can it be more crisp as i flow through the powerband? what changes can i make?

THANKS

 

[bill kdx nj]

will a 42 pilot give me more torque down low?

 

[ignition retard]

Does this bike have a powervalve? If it does, maybe try cleaning it and checking for proper operation. Also check the reeds, maybe repack silencer. Dented pipe? Hows the compression? Check the sparkplug (search for "plug reading 101" or something like that) I'm pretty sure that jetting changes will affect the bikes performance with regards to throttle position not rpm. Also you could try riding a known good '89 kdx, perhaps your mental image of '89 kdx performance is skewed.