Hey folks,

I'm new to the forum, but not new to the xt and the never ending problem sourcing with it.
So to make it short and straight to the point....I've got a problem with the bike and it's been persisting for the past couple of months.

The problem:
The bike either misfires or doesn't get the right amount of fuel going to it, at around 2000-3500 rpm. It idles great and doesn't have any problems running good on choke, but as soon as you shut the plunger back and attempt to give it throttle, it bogs, misfires and throws tantrums. It starts no problem at all, just press the button and on it goes, it may need persuasion on colder days with the choke.

The remedies:
What I have tried so far is to:
1. Change the ignition barrel ( there was an attempted theft on my bike so they cracked the barrel )
2. Change the battery
3. Change the Reg/Rec (reg/rec failed to charge my battery because the pins got corroded due to the salting of the roads ( UK ))
4. Change the relay ( for the heck of it, it was cheap )
5. Swap out with a 550s carbs ( a friend let me try his 550 carbs on and the bike started up and ran no problem, but it would still do that misfire/bogging thing )
6. Ultrasonically clean my carbs ( properly cleaned them out and blew out everything with compressed air )
7. Re-build the entire carb with new jets and o-rings ( apart from changing the diaphragm on the second carb (there are no holes/tears/stretch marks, just no sign of wear on it) )
8. I've ordered a second hand XTZ660 (tenere) carb 4000 miles on it, will need cleaning, but should be a straight swap ( I'll try it and see if it does that still )
9. I plan on checking the stator and pick-up coils, maybe tomorrow if I can get some guidance on it.. :] need help here with what to look for
10. The last thing I can possibly think of that would cause this is the CDI unit...unfortunately I do not have another one to try and they are quite expensive, I need options here...anyone? EDIT (I was wrong here the correct terminology for this make, model and year is a TCI unit)
11. Forgot to mention, I also checked the valve clearances to make sure that its not from air blowing back into the carb from the valves
12. Also the obvious air filter is not the issue here either, it would not cause the bike to act in the manner as it does, at that specific rev range, I've also ran the bike without it and it's the same issue.
13. Changed the intake manifolds as well (so they are brand new and I sprayed starting fluid around to look for air leaks...no leaks)
14. New ignition coil
15. New spark plug cap
16. New spark plug

Further:
I have documented the symptoms of "the problem", please find the video [{HERE (CLICK ME)}].

EDIT:
Sorry forgot to mention, yes I changed the ignition coil and I've tried 3 spark plugs, 2 old 1 new.
Everything inside the carb has been cleaned and replaced with new parts. float height is set to manual specs at 26mm.
The sync is set per manual as well, 5mm on the first carb just as the butterfly valve is rising on the second. mixture screw was adjusted for 3.5 turns out and then altered once the bike warmed up to 4 - 4.5 turns out.
Both slides operate freely and smoothly.
Also the gas tank is completely free of rust and is clean on the inside.
All the hoses that connect the carb parts to each other are clean and in good condition, same with the fuel line to the carb.
No kinks in the hoses either, the flow of fuel is unrestricted.

EDIT 2
The details of how the bike operates:

Engine cold
When the engine is cold, it's a bit difficult to start, but with the choke on it will fire up. It may die for a second, but it will start again no problem.
When the engine is cold, giving a bit of throttle will make it sputter and misfire bad, and it will not be able to go over the 2-3.5k rpm or even die. Unless you put the choke on, then it goes to 3-3.5, and you can drive it on choke, but obviously its just counter-intuitive to make the engine do that.

Engine hot
When the engine is hot, it's easy to start, both with and without the choke. It will rev higher when the choke is on and the engine is warm at 3.5-4k rpm.
When off the choke if you blip the throttle it will go over the 2-3.5k rpm and can stay higher, but if you go slow on the throttle it will die ones it reaches that rpm range.

The specifics of the pick-up coil.
Results:
Engine cold - 225
Engine cold, Ignition switch on - 250
Engine cold, idle - 270-300
Engine hot - 255
Engine hot, Ignition switch on - 282
Engine hot, idle - 310-340
Engine hot, throttle - 350-600

The jet sizes that came part of a kit
Jet kit..............................Original
Main 130..........................130
Secondary 110..................104
Pilot 50..............................48

Hi and welcome! Did you remove and clean filter inside carb? Float height correct? New spark plug? Change the ignition coil and spark plug cap? And adjust the sync on the carb?

So can you ride it around at low revs/ speeds ok? Like on 30mph roads? If so i had a similar issue and have just found that removing the snorkel and a DNA air filter fixed the issue for me so was running too rich and not breathing right.

Thanks rock !

Sorry forgot to mention, yes I changed the ignition coil and I've tried 3 spark plugs, 2 old 1 new.
Everything inside the carb has been cleaned and replaced with new parts. float height is set to manual specs at 26mm.
The sync is set per manual as well, 5mm on the first carb just as the butterfly valve is rising on the second. mixture screw was adjusted for 3.5 turns out and then altered once the bike warmed up to 4 - 4.5 turns out.
Both slides operate freely and smoothly.
Also the gas tank is completely free of rust and is clean on the inside.
All the hoses that connect the carb parts to each other are clean and in good condition, same with the fuel line to the carb.
I will try a new spark plug cap tomorrow, since its 23:00 ...don't wanna be a dick to the neighbors ^^

It's the opposite I can ride at high revs, but misfires and throws tantrums when I attempt to cruise at 2000-3500 rpm, that is if I am lucky enough to get it off the line without the choke.
It's not that andy, definitely sure on that since, you can see the bike is running without the side covers for the airbox.

Its 2,5 turns out and was it not 7mm gap?

I tried the manual specs at 2.5... that didn't work for me, it may be because of the aftermarket exhaust it's basically a straight pipe. But yeah it seems to work better at around 4 turns out. You are right it is 7...might need to come back to that one

Well i have aftermarked exhaust and KN filter and still no problem 2,5 turns, it only works on low rpm. Maybe you need bigger main jet, what size you have?

The jets came as part of a repair kit

Primary 130
Secondary 110
Pilot 50

check spark plug for colour if its lean, would try the 140 and maybe do the 120, dynjoet kit is 115. My bike runs perfekt on this kit.

the spark plug is good, neither white nor completely covered in carbon, it's dry as well, it's burnt halfway through the tip so I think the jets are good
Plus it ran on the 550s carbs no problem, but it was still doing that misfire thing

A suggestion came in saying it could be the pick-up coil, anyway to check it:?

Pickup coil resistance: 184-276 Ohm at 20·C (68·F) (Blue/ Yellow - Green/ White)

Measure in normal temp and then heat it and check again.

I just went and measured the resistances on the pick-up coil.
Results:
Engine cold - 225
Engine cold, Ignition switch on - 250
Engine cold, idle - 270-300
Engine hot - 255
Engine hot, Ignition switch on - 282
Engine hot, idle - 310-340
Engine hot, throttle - 350-600

your thoughts :?

Its in range as you see, think back when did problem start, have you done any changes before this or did it just start over night? Open CDI unit and check all connections.

Think it could be the TCI?
the advance curve


EDIT
I think you are right...my reg/rec died and it didn't charge the battery, so I got stuck in the middle of nowhere when that happened...hahahah how lucky...anyway fortunately for me I asked a guy to give me a push and I bump started it...at the time I didn't know what the problem was and why my battery was completely dead, now that I look back on it, what happened was that the reg/rec failed and after that bump start upwards of 20V were going into the TCI...if that is possible...I think this may have damaged it

But honest to god I cannot remember how the problem started

Its hard to tell whats doing it, try find a box to test for your bike or buy a spare. Its never wrong having double of all the parts for easy fix of problems that takes hours and days to fix else.