Bike Hesitates on take off, then kicks in and takes off like

BIKE HESITATES ON TAKE OFF, THEN KICKS IN AND TAKES OFF LIKE WILD FIRE.

This is from an 82 xj750J.
Bike hesitates on take off, then after a second or two, kicks in like it just lit the afterburners and almost throws you off the bike.

Once running and moving along, it negotiates all up and down shifts with the power and smoothest one could ever wish or ask for.
And as for the top end, that's no problem at all. Runs like a *aped ape.
Although I don't like to lug an engine without an appropriate down shift, I even slowed it down to 20mph in high gear with a passenger, turned up the wick, and the bike responded by almost bringing the front end off the ground.

I took the 4 fuel bowls off of the carbs, expecting to see a lot of gunk, that may be fugging up the lower speed, or enrichment circuit through the starter jet, but found none.
In fact, I was so surprised that the bowls were that clean.
But as a precaution, I did the cleaning and carb cleaner spray test to make sure the starter jets were all clear, while the return hole shot it back in a large stream of fluid.

QUESTION: What's the progression steps of these jets in the normal circuit of these carbs? I.E., Starter jet, pilot, main etc?
Since the carbs looked so clean and even the 4 carb slides move with no trouble at all.
So therefore, I didn't want to go further without pin pointing the problem of this hesitation I have on takeoff.
As they say, pin point the problem, and don't fix what doesn't need fixing.

If this is any tip; I can reve up the engine to a greater rpm before take off, and then have no problem at all with hesitation.
I presume by doing so, I then went into a higher fuel circuit that kicks in.
I'm only guessing, so you see, I do need some expert advice or suggestions.

And thanks to any and all for any conscientious feedbacks!
As I'm sure others have had this problem, while finding and pin pointing the solution.

P.S. From new, with only 29K on speedometer, and even though there is a little cam chain noise, it's hard to believe that the timing is momentarily off, when you consider how well the bike runs otherwise.

 

just a guess here. maybe your mixtures need tuning maybe try a carb sync as well. not a pro here but ive had a couple experiences with things bogging on the start due to mixtures.

 

How's the charging system?
I know that sounds unrelated but I had similar symptoms with my maxim x.
At low RPMs it would hesitate and lag until I hit about 3k then it would take off like a rocket...usually unexpectedly!
I kept thinking it was fuel related until I checked the voltage at the battery: Turns out, I was only getting 12.8v max at 4k rpm, and 12.4v or less at idle.
Cleaned all the connections between the alternator and rectifier and voltage regulator.
Bam! Problem solved! 14.4v at 4k rpm and a steady 12.8v at idle.
No more hesitation! And now it only takes off like a rocket when I make it, not unexpectedly.
It's worth a shot. Pull out your meter and check it quick...all you have to lose is a few minutes.

 

Have you set your valves to there proper specs? You may want to pull the carbs and clean them well, Do you have an inline filter if so you may want to change it, is your pet working properly?

 

If the bike has 29K on it and nobody has ever checked the valve clearances that needs to be done immediately even though it may or may not be contributing to the issues.

You're going to need to check your sync; and if the valves aren't in spec it will be a waste of time.