Honda Hornet Cb600f 2003 carb ver issue.?

My motorcycle loses torque between 6-12k rpm regardless if the throttle is being fully or progressively opened. It seems like it loses power for no reason and slacks for a sec.
For example:
Torque graph ———————-_____——~~~~__–~~~~_-~~^
RPMs. —-> 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

My motorcycle loses torque between 6-12k rpm regardless if the throttle is being fully or progressively opened. It seems like it loses power for no reason and slacks for a sec.
For example:
Torque graph ———————-_____——~~~~__-
RPMs. —-> 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13

This weird behaviour comes up randomly throughout the rpms.
I have replaced following parts:
Spark plugs
Oil and filter
Air filter
Clutch plates
Coils
Used PROFI fuel max carb cleaner
Cleaned the vacuum s breather tube
Drained the tank and carbs
Cleaned the internal petrol filter
Tried different fuels 95-99 unleaded
Replaced the battery

Any suggestions what that might be? Sync? Valves? Faulty Choke? Dodgy carb float?
Please help me out. This thing drives me crazy.
Thanks to all.

Other answer:

Marcin:
When were the carburettors last balanced? Is there any variation at idle?

According to this graph (green line)

http://motorcycleperformanceanalyzer.com…

your dips in power occur at the predicted points peak at 9,200 drops gently to 12,200 after which it drops like a stone. Admittedly this is not the same year as yours.

Candid Chris:
Added a few maintenance parts. Okay.
Do you know how to tune that bike? A Shop Manual can help.

Trying to figure your issues out is a crap-shoot, don't know what you did or don't do.

Good guess would be valve related, but see above.

Firestormer:
Inline 4 engines always have a mid range dip in the torque curve. You will find it in every dyno chart you could find.
Your bike sounds quite normal. Stop stressing and just go for a ride.
Deacon K:
hi
Timbo is here:
Torque and power are different. Engines tuned for high performance will produce max torque at lower rpm than the max bhp figure- its normal

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