new to site sputter at 6000 rpm

[Jar3d200]

Not sure what to post to couldnt find mechanics 101 that I saw on other ppl.s anyways riding my first bike this year it is a 2001 katana 600 got it 2 months 3 months ago with 21000 miles on it ran good for first 2000 miles. I rode it 250 miles 6 hours of almost straight riding except to get gas about half way through the ride it started sputtering I ran zome lucas in the tank last week then brake lever broke so it sat for a few dayz started it a little smoke came out of tail pipe yesterday I replaced the lever tightened the chain and did a oil and filter change the sputtering is better but still there in all gears between 6 and 7000 rpms before I bought also had needles and carbs cleaned and suggestions would be great I get popping when releasing throttle after 7000 rpms it runs like a champ bought the bike used and dont know much about bikes got vance and hines full exhaust I beleive guy at motorcycle shop said its faster then most katana 600s he has ridden not much low end snaps loose around 7000 rpms and all u seen is my tail light

[92xjunker]

Have you replaced the fuel filters? Popping is a lean condition.

[Jar3d200]

No just the oil and oil filter so far

Looking fuel filters up now gonna go to bike shop tomorrow try to pick one up anything to help me figure out how to change it im new to bikes manual or anything. Anything else u can think of thats not to hard or expensive at the moment

[GSXFJim]

Download the manual from the wiki

[Jar3d200]

Ok will do