Honda nighthawk 400 sputtering/hesitation?

Hey so I have a quad (atv) and it has a Honda hawk 400 engine. It's carbureted. I just cleaned out the carb and got new spark plugs. It starts up first try and idles perfect. But it has very low power at low rpms. I can go full throttle and it still doesn't give much power. Then at about 5krpm it sputters and hesitates them kicks in and puts down a lot of power like it had boost lag. That s the only way I can really describe it. Any help? I just want all the power it shows after the hesitation to be there all the time

Whenya rebuild a carb ya take it completely apart, soak it in carb cleaner, penetrate all of its little orifices, install a new metering needle and main jet, new floats and float needles, new o-rings, new bowl gasket, and adjust the floats. Thenya set it up like it sez in the shop manual, and do that tuneup thang. Oh yeh… While stuff's apart you check the fuel flow, the petcock, and install new fuel and air filters. Sounds like ya mighta skipped sumpin.

You have cleaned out the enrichener circuit but not the others.

The slide diaphragms wear out and leak air, causing those symptoms.
Disassemble the carbs and thoroughly inspect them.
Also carbs out of sync can reek havoc

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