do i have a carb problem

76 kz 400 missing/popping above 6000 rpm
Below 6k it runs good. Seafoamed it and it has
Fresh plugs.

Any ideas.... thanks guys

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one thing you could do is post a photo of the end of the spark plugs.

how long has it been doing this?

did it start immediately AFTER you changed something?
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It's been this way since I bought it. I haven't changed any motor stuff
But did notice it has a K&N filter
In the air box. I'll get a plug out when I get home from work....thanks

sounds like ignition as on 6000rpm you're already on main jet. Could be fuel delivery too. Check flow out the tank by disconnecting fuel line and opening the petcock. You need a steady flow, not dribbling gas. Put a big rag under the tank or take the tank off. You dont want gas on engine.

If it ran good before thats prolly it. If you just got it, it could also be float height or needle clip position.