2001 kdx 220 starts idles great no power stalls out , floods

2 things. come to mind.
i check the distributor advance works to spec with my timing light (strobe)
if that is ok, its a carb issue.

carbs fail for many reasons, (mostly gummed up inside)
we clean them. that fixes them. (with a kit)
I only have this for symptoms, and is not good.
MAJOR HESITATION AND STALLING OCCURS
does the engine have full power up any hill wide open throttle
is the Hesitation only a short time then catches up.
The carb (not stated P/N or brand) has jets, the if gummed up
will cause lean running.
so will any power valve jet.
ever tune it up. new spark pats, rotor all the way to spark plugs.
bad spark , loves to fail under load, that is its , magic.
carb>

1. low float bowl levels.
2. low fuel pressure causing above,
3. bad float valve , sticks closed and starts bowl of fuel, causing #1
4. Gummed up jets.
5. Gummed up emulsion tubes in carb body.
6. Choke stuck on, causing flooding,
7. Choke dead causing hard starts . (stuck open)
8. power valve clogged.
9. Highspeed accelerator pump bad, causing only sight hesitation.

my guess? based on 1 word "stall" its #1 to 3 or 6.
black spark plug tips would be #6

or if black sparks, the float valve is stuck open flooding engine and stalling.

we can go for days on carbs. but will not.

make sure all filter r clean or new

Clogged idle circuits in your carbs. Clean jets and passages.
You can try suck dirt out, therefore: Screw the idle mixture screw out ( almost totally ), give full throttle ( 1 second ) and then hold your hand against the carb air intake.
This will give maximum suction and can suck the dirt trough tje circuits.
Also, first drain the carb(s) to be shure there is no water in it...

Then your carb IS NOT CLEAN or IS NOT ADJUSTED PROPERLY. Flooding is a direct result of your carb having issues.

Thank you for contacting FixYa with your inquiry.
Low power or stalling at start is usually air/fuel related. You have taken care of most of the things that effect the bottom end power band. Some other things you might consider:

1. Check the air vent tube on top of the tank to make sure it's not pinched or restricted.
2. Clean the fuel tap. May have sediment or debris. Some have a filter screen. Clean it.
3. Clean the air filter and air box. Check the rubber boot for cracks or air leaks. Clamp??
4. Exhaust system - Check for leaks or fiber fallen from the muffler.
5. Check the diaphragm or reed valve for cracks or reed problems
6. Check the timing or fault with the ignition system. Is something loose.
7. Screw in the idle jet all the way and back it out to 1 1/2 turns.

Jetting: (Tons of options with a Mikuni) In general, the main jet is for high rpms and top speed running. Needle effects the mid range to about 3/4 throttle. Idle jet effects the bottom end. 3 sizes exist 20, 25, 30.
Drill down from this link for part numbers: http://cyclehuttktm.com/FicheFinderNew/FicheFinder.aspx 2010 > 65 SX > ENGINE > CARBURETOR
Let us know if we can provide further information.
Kind regards,
TF

Check the fuel flow by opening the drain screw in the bottom of the bowl. Should run freely. If that's not running freely, clean the tank and petcock. Also check the gas cap and make sure it's venting properly, if that's plugged it will affect fuel flow. If all that's good, start checking compression, reed valves etc. Get back to me with any more Q's.Good luck!

I had a sticking throttle cable as i turn it would idle up

may want to look at changing out the reeds

check engine oil and change the oil seal of engine

try placing the reed spacer between .reed assembly & cylinder, also try an adjustable ignition stator plate, set at +4, k & n air filter, open air box.replace T.O.R.S. eliminator system w/ a cap & cable, and idle air screw install kit, also a pipe tuned for more torque(bottom -end/mid range) blasters dont have a lot of power on bottom end and the engine needs to rev to hit power band.cylinder porting,240 bigbore kits, & +4mm stroker crank assemblies are good performance options.