This Is Why You DON'T Buy a KTM Dirt Bike ($1300 KTM 450 Find)
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- Опубликовано: 7 сен 2024
- I take the KTM400exc for the first test drive since buying it. #KTM, #Horrible,
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Dont be affraid of rejetting a carb! The stock jetting isnt always the answer. Even a couple degree change in the temperature can make it bog. If you feel like it needs a smaller one put one in it.
JD jetting makes a great jet kit
I agree. Definitely worth a shot. Worst that can happen is that it doesn't ride any better but hey it's already running pretty bad as is.
I agree. the issue that I have is that you shouldn’t have to, unless you plan to operate at extreme altitude(s). I believe many OEM suppliers & aftermarket producers could do a much better job at machining & assembling parts with tighter tolerances. I’ve seen big-name Japanese automotive part suppliers’ quality decline in Honda/Acura and Nissan engine & transmission manufacturing over recent years, so I imagine that their power sports parts/component manufacturing has followed suit. I was in the mass pro auto industry during & years after the tsunami, but the out-of-spec-parts increase began well after their infrastructures were restored. I fear the worst is just beginning.
Agree with this
They are little lean on factory jets because lot of these was street legal and had to pass emissions
Another vote for stator electrical issues especially with it not registering above 14v charging.
Definitely sounds like an ignition issue. Fuel delivery problems are seldom intermittent. Start with the simple stuff. Disconnect the stop/kill switch from the primary lead of the ignition coil and test ride the bike . If problem persists, unscrew the spark plug boot from the secondary ignition coil lead and check the resistance of the boot. It should be close to 5k ohms. 4.5 - 5.5k is fine. Then before re-installing the boot, trim the secondary coil lead back 1/2". Make sure the lead is long enough to do this. There have been thousands of perfectly good ignition coils replaced when the only problem was the spark plug boot or the connection between the boot and the secondary coil wire. Other than these checks, it's on to the stator, pick up coil and CDI unit.
Good luck!
Had a very similar issue with my bike , turns out it was bad wire in the coil and a few other wires on the bike that had corroded over . Fixed all the wiring issues and it ran perfect
I can’t justify saying that the stator isn’t an issue, but I had issues with my 2002 520 falling on its face like that. Checking that the throttle position sensor is rotated to the optimum position helped, because that adjust the spark timing as the throttle turns. The thing that seemed to help the most was dropping the needle in the throttle by raising the clip position two spots, reducing the flow of fuel as you open the throttle further. Really hope you figure it out, love the work you do, keep it up!
throttle position sensor on a carb?
@@mikenike776 ruclips.net/video/0lBPDrjAwqA/видео.html
This is why you don't buy a KTM dirt bike: you don't know the difference between a high/mid-speed miss and a 'rev limiter'...take the advice given, check the TPS,, but since the plug (wrong AutoZone special) is black and sooty, maybe check the needle position and/or the main jet size. Just because 172 is 'stock' doesn't mean it's right for your setup. It's just a starting point....
My approach would be to start by leaning out the main, so it pulls hard at wide open throttle (WOT), and then adjusting the needle to smooth out the transition between part-throttle and WOT. The pilot already seems fine...
Just a thought.
Bury it next to the Yamaha!
Sounds exactly like what my bike was doing. And all I had to do was reset the ap timing and go down a size on my main jet, now she runs like a dream.
that's an oversized fuel tank...why they made a hole for choke access...it isn't weird... or stupid...a simple solution to make working choke easier while allowing more fuel capacity....
Check valve clearances, and I would also pull the stator cover again and check the stator voltage output at the connector itself where it connects to the main harness. That bottom coil @ 17:00 mark in your last video looks very dark to me. It could be something simple as a bad electrical connection, someone was obviously messing with the electrical at one point based on the headlight wiring. Yes it does appear to slowly build up a charge, but that doesn't seem right. As soon as it starts up, if its charging properly, it should be reading high 13s - low 14s steadily, it shouldn't take a min or two to climb to 14. It should just read and maintain whatever it is outputting for voltage. From a quick google search, yours has symptoms of a dying stator, which can also cause engine running issues like yours is having. So I would find the stator resistance/output specs and start troubleshooting there. If none of that helps, then I would start looking at re-jetting the carburetor.
@martin barr's CRF450 not necessarily. The ktms didn't really get hard to start if the valve lash was too large unless it got to the point that the valve wasn't opening. And it seems like its getting a little warmer than joe wants it to considering he was complaining about boiling coolant when he rode it.
See my comment, I had the same problem because my bike was running too lean. All the time I tought was rich condition because of the black smoked spark plug. The black smoked spark plug can be confusing.
I agree. Battery should be charging at well over 13 volts the instant the bike is started.
@@Mr.M1STER True, whatever else is wrong with it that is not right for a start.
Valves
I have an 08 sxf and the jetting of the flat cr carb always gave me issues. Either around camp or at the top of the mountain. I’d always be swapping jets .
Once I switched to a lectron, “kinda felt like cheating “ I had instant power everywhere.
Lots of love bro , love the vids
If it truly is a 2002 400EXC then the exhaust is wrong. The 2002 400 had two pipes out of the cylinder all the way to mid pipe before it went to one and into the silencer. Also, the muffler does have a spark arrestor in it. I owned one since new and just recently sold it for a newer model.
A JD Jetting kit would wake that bike up, but I agree with others that the bogging issue is electrical.
That year carb was difficult to get the pump set correctly as you have to bend a tab. Took me many tries to get it right.
Good luck!
Ever heard of aftermarket exhaust?
@@rposton919 aftermarket pipe doesn't change the head mate😂😂😂
Two pipes come straight out of the head on 400 exc so perhaps that's 450?
This era ktm was known for issues… all sorts of issues…. The new models are superior machines
Amen that
@@PearlyS10 pos this thing is god dammit!😮😱👁👀👁🤯🤪😮🤔🤔🤔
Lol last vid everyone was saying that era of ktm was “highly sought after” what is it with KTM riders lol
@@urbanitesgarage3299 they were saying the 2003-2007 generation were very sought after, because they are. I’ve seen several of those motors with thousands upon thousands of miles on completely stock intervals, only oil changes.
@@mw4518 im cutting it close with a 2008 lol
I had a 2002 EXC 300 2 stroke when I was a kid, I loved it! I was so comfortable riding it. I was racing my CR 85 before, when I switched to the KTM I noticed and felt a major improvement in my riding. I miss it, it looked exactly like yours.
I have a 99 380 and it’s amazing. So much power, it keeps up with the newer 250’s and 300’s. It Doesn’t give me much trouble it’s pretty reliable. I hate how he said “this is why you don’t buy a ktm” he bought a cheap bike that obviously hasn’t been taken care of, of course it’s gonna be a basket case. If you take care of them they’re great. If you buy a cheap one that’s been abused obviously your not gonna have a good time.
@@jakobsmith3772KTM is trash
I had a failing stator and it produced the exact symptoms your dealing with. It would start up and run good in the low rpm’s but would break up at high rpm’s like seen in the video. The stator does seem to have an issue with it based off those charging voltages. Should immediately jump up in voltage, not a slow climb as seen on your bike
I agree with Model RC. 13.0 volts is not enough. That would cause your rich condition also. Not a KTM guy, but I would think the voltage should be 14.0 to 14.5 with it running.
I had a sx-f 450 and the voltage was 13.5 - 13.8
@@danielspataru6372 That voltage makes sense IMOP.
same, my honda trx300ex had that problem ran fine but then sometimes it would limit at 80kmh 2min later 92kmh then 70 felt like it had a rev limiter, then drive fine, stator was all dirty and i just changed and never had that problem again (i did but the spark plug booth moved and didnt make connection but that was a easy fix)
number 1 ya shouldnt leave your dog out in the rain in the kennel better invest in a invisable fence or take him inside to me if plug is good its stator or coil / ignition
Recheck your valve clearance. Could be as simple as your intake is too tight and not clearing all the fuel into the cylinder when it opens causing it to pile up and get more and more rich as it runs. Other than that the timing could be slightly off, maybe the woodruff key bent slightly when you were having those one way bearing issues.
I'd check you're intake valves miby something is slightly off as there normally decent running bikes over engineering definitely with ktm but it seems like it will definitely be a small problem
Leak down test
I've never owned A dirt bike that ran in my life. I always fixed.& Repaired.& Worked on them for other people instead to enjoy instead of myself on that part of it all tom.
The hole in the fuel tank on KTM bikes for the choke is just for the extra fuel capacity of the tank, not "over-engineering" in my opinion.
Exactly correct. When you only have a 2-ish gallon capacity in the first place, that extra capacity could be the difference between riding home, or pushing the bike home.
Checkout the vented fuel tank gas cap to it maybe plugged in the tip nipple to by chance from dirt.,or dust.packed inside of it to tom.
20-year old bike. For a sanity check, try a quick leak down test just to verify there's no issue with valves or rings before getting too involved with carb adjustments or electrical system.
KTMs are awesome bikes and require experience to keep them maintained. You cant slop shit around on these.
aka they break very often and have reliability problems
New Regular rectifier - Cheap as chips - (Voltage should higher than that), also voltage drops slightly if anything when you rev it up - Also compression doesn’t last very long on the EXC’s - New rings and yer good - Get yer money back on that sprag clutch bearing - Still a good buy though.
Got to be electrical, test the stator and cdi
Typically manufactures give rich jetting. So the average Joe don't blow them up. Maybe this machine just runs rich. Id try dropping the jetting. The accelerater pump you usually don't get enough squirt. When they fail they are not squirting enough. Today's ktm are top notch. All the early (02-04)4 strokes the manufacturers were trying to work out the bugs of competitive 4 strokes. Not just ktm the big 4 Japanese too
I have A 2000 400exc it's the carb, I never could get it to run right I bought a rebuilt carb for 300 and sold mine for 200. Best 100 bucks I ever spent. My original carb someone had added a long fuel screw and that model carb wasn't even designed for it. Made bike run super rich.
Sounds like a leak around the sneezer pin. The penal anacular spring should be at least 3 cat turds out and torque setting should be at minimum 30 uga dugaz!
Dude??? I agree with your penal anacular spring settings, but 30 uga dugaz? That's way too many.
My banshee used to do this same thing it was from a stator wire running along next to the exhaust and it would start up and run great until it warmed up then sputtered only on acceleration the wire would heat up and loose continuity and make it run poor
Or pick up coil get's hot and fails.
I think it runs like shit because you have that poor puppy locked in a cage in the rain.
So the moral of the story is if you have a KTM, take it to someone who knows what they’re doing
Or...buy Honda.
Never own one. Austria is not Germany.
@@scottnathanphoto Germany makes a competitive dirt bike? Figure out why not.
@@EarthSurferUSA I had a 990 Adventure. It was trash and always broken from new. Same goes for every KTM owner I've ever known, (dozens.) I had several BMW's including a GS Adventure. Never a single issue. Clear?
@@scottnathanphoto own 3 ktms best bikes ever
Hi had an EXC 520 - I converted it to a Supermoto with stiffer suspension, upgraded brakes, 17 inch wheels front an drear, road tyres and different sprocket ratios and it was AWSOME!!!!
Most of my friends take their bikes to the mechanic because they cannot figure the s*** out but you are a superstar God!
Take off air box cover. I put an exhaust and valves in my 450 and couldn’t figure out why it was doing exactly what your bikes doing. I took off the air box lid and it became an animal. It was restricted and wouldn’t rev out.
I've had something similar happen before. Turns out when I replaced the diaphragm on the carb, i put the fuel needle through the retaining clip instead of under it. It caused the bike to bog under load. You can also see if you can adjust where the fuel needle sits on the clip and check for tears in the diaphragm.
Could be a coil problem sounds like spark is cutting off
Hiya. My untrained but been mucking around with motors my whole life gut instinct says ignition issues. Also in my old shop we used to say KTM stood for Keep Throwing Money lol. Dont know what KTM parts are like in the US. But here in NZ they are stupidly expensive. A set of genuine valves and springs for ya 450EXC would be over $1500!!!! So yeah, hardly ever used genuine parts in the things.
My 2010 400xcw sounded like that right B4 it dropped a valve locking up bike.
Head alone 800$. Oil was clean but there was shards in my airbox
Had an 04' 450 EXC that did much better after replacing the mid-body gasket. Just a thought.
Same. ‘05 525 mid body gasket
Personally I would check to make sure it has a stock cdi on it and check the stator output as others have already said.
Check the pick up coil.,or the points to if that we engine has them on it to. They set between 0.15 to 0.20 thousands of A inch on top dead center to just about to open up. Accept still closed off until the crankshaft is rolled over again to fire under pressure.
I had that problem on my 110cc pit bike and it was too much gas coming into the cab try closing on the carburator flotor .
I got a 03 KTM 450 exc in late 02 Worst bike I ever had, just did not like it. power delivery sucked suspension sucked everything about the bike. By then I had ridden a few 400 exc and ended up getting a 06 400 exc totally different bike, one of the best race bikes ive had!!
PS: KTMs are Race bikes (Not trail bikes) They are designed for racers and racing and strict maintenance intervals in heavy race load (HR"S). A lot of the thing you don't understand why there done are answered by this alone.
a lot of times I go too far vintage guy and I forget to think about you because you are the main attraction here this is your channel you are the SUPERSTAR!
I think the click after shutoff is part of the electric starter mechanism. Also the 18 inch rear wheel may help you determine 400 or 450.
Shouldn’t a battery be around 14volts while bike is running ? Maybe stator is shot
According to plug definitely running rich but I’d almost be willing to bet it’s maybe an intermittent spark issue on acceleration. My rmz kinda did something similar to this and it was in fact electrical
Black smoked spark plug not always is because running rich, I can be because is running too lean. It can be confusing, but I had the same problem, the plug was black and smoked. It took me 2-3 weeks to figure it out, always I was thinking is running too rich because plug, but NO was lean condition. After trying big jets I coudn't belive is running too good, starts with no choke and rev it out completly.
In my days of racing motocross it was always the ktm,s that broke down. Seems nothings changed.
Everyone i knew that has had a KTM worked on them as much as they rode them. Every now and then you get a good one that performs well but very rare.
You need to route the throttle cables correctly they should go between the handlebars and the tank I can hear the throttle sticking when you turn the bars.and it actually sounds lean at higher rpm definitely do the mid base gaskets on the carb it's sucking air .
If your coolants bubbling that’s leaning towards a lean condition
The world needs leadership vintage guy and you are a perfect example of high-performance!
I'm a bit surprised that the oil hadn't been diluted with fuel. When fuel remains in the cylinder, it seeps down past the rings and into the crankcase. The guy must have changed the oil shortly before selling it to you.
Yes he did change the oil right before selling it to me.
@@2vintage you no why they do that rite ? to hide sh*t
Could the previous owner have changed the float hight , attempting to stop the fuel from leaking? What notch was the clip for the main jet needle in?
I agree. It points to a possible float height problem but maybe set too low.
18:39 why does he just have a puppy siting in a cage outside in the rain listening to a loud bike?
That click is the starter gear. Sometimes the motor spins backwards a little bit when it’s shut off. It’s completely normal my 2021 Crf250r does that and so does all of my other buddies bikes
I had an ATC 90 I bought as a box of parts. Got it all together and it never ran right, like your KTM. Turns out the box of parts came with two ignition coils. I picked the wrong one. Put the other one in and it ran perfectly. .
Sounds electrical. Like the stator. Not giving constant spark.
Air fuel mix ain't right he has to hit throttle to bringing idal down more than likely pilot jet to lean at idal and needle set to high making it run to rich in full throttle also always good to check valve spec to
This bike has a fcr39 carb.
Those carbs separate in two pieces in the middle, a really complicated gasket handle all the idle chock circuit
Those gasket go bad, you need to change them, that's probably your problem as you are trying to tune the carb and nothing you do improve de situation
This was the gasket in the little metering block? Kind of a mushroom shape. I have heard of this. I think it was on a Suzuki DR. I avoid fuel with alcohol in it. I think it deteriorates the rubber. My 2 cents.
I wish I had a family like you vintage guy and the only reason I am so fantastic is because I never listen to my mother!
Correction, don’t buy ktm FOUR STROKES! The TWO STROKES are amazing!
replace mid body carby gaskets. if it has a slide check the gasket or o ring on that. I have a 01 wr250 that would still randomly when warm, miss on load and sometimes not start because of a bad mid body gasket and slide gasket. it wasn't even that bad but enough to make it do several weird things. another thing to check is try another coil in it. if the coils going bad it can break down when they get warm. process of elimination now.
Always check valve clearance when you buy a used bike. Most people have no clue about how often they need to be checked or even check them at all.
There are many factors that can contribute to poor performance like that.
It is likely a combination of problems.
A few things that you can't at first see are:
• Cracked spark plug
• Corroded spark plug wire
• Dying ignition coil
• Bad CDI
• Blocked carburetor passages
• Intake manifold leak
• Blown head gasket
• Cracked cylinder head
• Burnt valve
• Cam lobe going flat
• Any number of other issues
If you look at the KTM, Haynes, or Clymer service manual, you will see there is a section that deals with trouble shooting. It guides you through the steps to solve this kind of problem. You can easily rule systems in or out as "the problem".
You could easily have more than one problem, that when combined lead to terrible performance.
Some of the KTM EXC's (Enduro Bikes) here in the UK had an option of a "long range tank" which yours look's to be one.
Also checkout the inline fuel filter for being plugged up with debris.&sludge build up. One more thing to checkout is the fuel tank line inlet port for fuel flow blockage to like from rust.& Etc.
Check the airfilter and intake track , if the carb is functioning as it’s suppose w stock jets and it’s pig rich then check the filter and intake track to make sure nothing made a nest or has it obstructed , if that’s Gucci time to check the valves and do a leak down test . I’ve seen cam lobes wear off which caused a similar issue .
I had a kdx that was old and the slide needle and brass part in the carb that meters it was worn out, no amount of jetting would fix the rich problem. Figured it out years later....
I had a four stroke that ran just like that once. Tried everything. Turned out it just needed a new spark plug, the one that was in it was causing bad misfires.
Not trying to be rude I’m Just curious, what all did you change?😂 normally the spark plug is the first thing to change when your having issues
Why do have that dog in that little cage when he has acres to run ?
The sound you hear when it shuts off is very common in modern 4 strokes. It's the decompression snapping back.
It sounds like an intermittent spark issue to me, possibly the plug wire. I had a 4 wheeler that was what it was.
I was going to say the same, try it at night and look for tracking otherwise try changing plug cover, wire cdi whatever.
Bike/engine diagnostics can be pretty simple if you just follow the basic steps and eliminate all the variables! ALWAYS drain and change the fluids (especially the fuel! It's an unknown quantity) draining the oil can give you a clue to overall engine condition. Inspect/Clean/Replace air filter. Do a proper compression test. Start with the cylinder dry! No oil, if it's low put a small amount of oil in the cylinder and retest. If compression comes up considerably your issue is "probably"rings and not valve related (4-stroke). Clean and inspect carb, if you're sure it's functioning properly, pull the ignition cover and check timing. In this case you have a charging system and it's not charging properly (low voltage) find out why! Inspect wiring harness and all connections. Buy a manual or research online and find the correct test procedure for the stator and coil. In this case I believe it's one of those 2 things but hard to say and only guessing without testing. The vibrations and conditions that bike components are subjected to can wreak havoc on wiring and electrical connections.ive also seen 4 stroke engines run erratically from improper cam timing ( excessively worn chain (although I doubt that's the case here)
Gotta be electrical. The plug could be black because it's still putting the same amount of fuel in but it's not firing so it's not burning off
It seems the throttle cable get pulled since moving the handlebars changes the rpm on idle... If its not the carb it might be the cdi
I had the same problem one week ago. It took me 2-3 weeks to figure it out. All the time I thought my bike is running too rich. I tried small jetting, but this was not the problem. The spark plug was always smoked. I tought it was burning oil and I changed the piston ring, agan this was not the problem. Maybe you don't belive, but all the time my dirt bike was running too lean. I rejeting the carburettor. And now starts immediately whithout the choke and rev to the max whithout any bog. I hope I was helpful and sorry for my bad english speaking, i don't know very well english language.
If you had the problem a week ago and took you two to three weeks to figure out then you havent figured it out yet. For another one to two weeks anyways.
Pilot jet to lean at idle needle setting or main to big causing to much at full throttle right
1 week ago the problem was solved
@@Mizman76
his english is better than yours..i understood what he said....and your joke too...
Discount the accelerator pump, see how that does. You should be able to unhook the pump lever.
Definitely too lean, thats why it surges at idle and cuts in and out. Make the air fuel screw more rich
did you not see the colour of the plug no?
looks like this bike has had a hard life, using large gauge amp wire for battery wires, the headlight isn't properly fastened to the forks ( doesn't even look like a KTM headlight, but a cheap aftermarket) no brake light etc
Try raising the needle in the carb slide 2 notches, if that improves things check the float height and set to factory settings then go back to the needle and set the best position by testing. Your problem is lean mixture not rich I think
the clicking when u turn off the engine is normal, i have it too
Always go back to what an engine needs to run. But it needs more than that to run properly! Air/fuel/spark. Air needs to be adequate, fuel needs to be fresh and metered correctly. And spark needs to be adequate as well. And timed correctly. Just because you get spark cranking an engine does not mean it's enough spark or at the right time for complete combustion. And it also needs enough compression for proper combustion. When you're dealing with a 4-stroke more variables come into the equation. Valve seal, valve timing and adjustment. And then there's always the possibility of air/vacuum leaks.
Why do you buy new plugs just because it’s carbed up?? Does no one ever clean spark plugs anymore? All you need is a fine brass wire brush. They last years if you just clean them and keep the gap set correctly.
It’s most likely running rich, so an air filter or carb setting issue.
Electrical is my weakest skill set. I'm always looking for ways to learn how to do this stuff, but I've never come across a good complete way. I want to know how to diagnose and properly repair the endless catastrophes I see on these machines.
You got a deal at 1300. I have purchased three different used KTM'S . The first one was a 400. The second was a 250 and the third was a 510. All was very good bikes.
I was never a fan of ktm to begin with! I had a buddy who a couple years ago bought a brand new ktm 450 2017 and we went to the track and he hit a couple jumps before the forks snapped beneath him on a landing and he ate dirt hard, the bike was maybe 2 weeks old. I’ll always be a Yamaha guy!
Sounds ignition related. It’s not bogging, it’s breaking up. Cdi or weak coil. Ohm out the coil and if it ohms out good replace the CDI. Sporadic and weird is usually CDI or in the automotive world ignition module.
Can't a KTM dealer tell you what it is from the VIN number?
I've never had a KTM (briefly ridden a couple which were good) but my buddy has had 2 (yes the ones I've ridden) and he always says "Great bikes to ride but bad bikes to own".
It probably is the jetting. It may be stock but it might need to he changed to the altitude your at. Because I bet that bike came from somewhere else out of the country and the guy didn't wanna mess with it so he just rode it with the messed up carb. You can also adjust the needle if that's a thing on 4 strokes lol I can't remember. I ride a 2 stroke now these days
My drz 400 did this plus cutting out , turned out to be the needle seat in the carb slide. Barb had snapped leaving the needle loose and bouncing around
some people might say take it to the dealership because they know what they're doing but I think you are better than the dealership!
I have a 2002 453. 525 jug on a 400 case. Ktm didn’t make the combination. Runs great.
Known as the best KTM that KTM never made. 450 with the 400 shorter stroke.
There is a rubber gasket in the "tower" of the carb spraying carb cleaner into it usually destroys it and it will never run right after.Accelerator timing can be a problem but not create backfiring like it does...
Recently bought a honda ct 90 for 250$ no carb or anything but I zip tied a battery to the side of it Cleaned the points and it had spark so I sprayed some starting fluid in the intake and it popped off for a bit needless to say I'm happy with it.
You must be a crazy hard worker because it is so hard to focus on your job well you are doing all the camera work!
If you can I'd test the stator and coil cold vs hot seems like it's either blowing out the spark or has compression loss through the head gasket or something and maybe it's causing it to give false rich plug readings.
I second the head gasket he says it's getting hot
See if the needle is stock needle and clip is in the recommended slot. If it is, I would try setting needle clip in the next notch up to lean out the mid range. If that doesn't work very well, I would put the needle clip back to to its original position - and then I would try going down on the main jet one or two sizes. As they say, "Make one change at a time."
I suppose it's POSSIBLE the carb pump is acting up but that the pump SHOULD not be an issue 3 seconds after the throttle is turned...unless there is something REALLY WEIRD wrong with it. That is, the bike was misfiring several seconds after you twisted the throttle, long after the pump did its job.
The carb has an accelerator diaphragm. It turns to crap. Had an identical bike that just got sold and it would bog on full throttle from idle. Ran wayyy better than that tho overall lol
Get a R&D flex fuel screw adjuster. Rocky Mountain has them. This will allow the fuel screw to be adjusted from the side. The starter is in the way to adjust fuel screw. When the fuel screw is adjusted correctly, throttle response will be better.
My ktm 525 my biggest problem was the mid gasket on the carb it ran before I changed those gaskets but not good after it ran great. Not the bowl gasket but mid body gasket on carb
My ktm 360 with a gnarly pipe had a bad bog. I ended up after many tries going with a 178 jet instead of the 172 and second notch on the needle. Try going way rich first with 4 sizes bigger.
You need to put nkg plug back into it and get rid of auto lite plug and rejet the carb