Depends on what model and restriction your bike has in place.
If its "uncorked", as in the restrictor in the airbox isnt present (brass coin thingy) then changing the tip to a racing tip helps allot.
Stock "uncorked" bikes run jets 65 pilot and 175 main. Check these !!!
If you take the baffle/tip out of the exhaust then up the pilot jet to a 68, it will start, run and blast like a dream.
for road use, many peopel drill holes into the airbox cover and cover with a fine mesh as it helps the engine breath quite a bit.
2001 NX650 Dominator.
EX - BMW Dealer Technician