I have a 04 600.I had the winter update done and it made a big diffrence but I would still blacken plugs every once and a while.I talked with my dealer and they said that they had some that still actted up after the update so they put a pilot let from a 700 in and it solved all the problems.So I put the 700 jet in and the bike ran great for about 2 weeks of plowingin very cold weather,now I can't keep the bike running when I fisrt start it ,it slowly drops in rpm and stalls and the plugs are extremly black.I tried adusting the air screwout 1 1/2 turns but it made no difference.But when I had first tried it I had the boot clamps loose on both sides of carb anb the bike started anb ran fine,when I tightend the clamp on the boot from the carb to the motor the problem started anb the bike rpms dropped from 1400 to 800 and it stalled.If anyone has any ideas I would sure appreciate it . Sorry for the long message.

 

Your stock pilot is a 45 and if the put a 700 pilot in its a 47.5 that would make it run richer. The main jets in a 600 & 700 are the same 155.

 

sp6, there is an update for the 600, have your dealer check the team tips for the 600 and 700. they will find all the parts needed. i assume the winter update they did was the breather hose?? the carb update consists of new needle jet, jet needle, main jet, slide spring.
as far as the screw you were adjusting it is the fuel screw, not air. also, what plug are you running? we have had pretty good results with ngk bkr7e & bkr6e plugs. check out the posts under "04 600 hesistates,backfiring.."