mid range miss

hey out there in thumper land. it has been a while since i have had time to check in on tt forums, been doing alot of riding and even a little jet skiing. i recently picked up a second 03 yzf 450 the problem is when i hold steady throttle like over whoops the bike misses. as far as i know it is all stock except for a fuel air thumb screw on the bottom of the carb i have tried adjusting this mixture but it does not change performance. where should i go from here?

the carb on the 03 is terrible IMO, it sounds like its too rich but would need more info, it could be the main, pilot, or clip and you might have to fool around with all of them and do a lot of testing to get it to go away. I had to try everything possible with jetting on my 03 and could never get it right - not only that but if it was close it would suck at very little differences in altitude and i ride all over the place. I finally put on an edelbrock 40mm carb and got it dialed in - i got sick of that dam stock carb

yeah my friend had to have his replaced by the edelbrock carb. he hasnt complained about it since...

Lean the needle one clip position (move clip up = needle down = leaner), should help, i had the same problem and this fixed it, i also went richer on the pilot jet from a #42 to a #45 now runs sweet. IMO the carb is fine it's just a matter of getting the jetting sorted to work in the conditions you ride in, same with any bike. :)

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