Yamaha wr 400 2000 model pulled apart carby to clean

It is slipping. These big yamahas normally have slipping clutches. Mine slips, I've just learned to baby the clutch. Make sure you are in the most comfortable gear for the speed you are running at. Avoid rolling on full power at low speeds in higher gears. It's the nature of these great beasts. Clutch springs are too weak in these bikes, you may consider an aftermarket clutch spring assembly. The "shudder"(intermittent slipping) is caused by glazing. Make sure you are using the right lubricants for your bike, some synthetics can cause problems.

1)Adjust clutch cable correctly, check
2)Pull the clutch assembly apart, if there is little wear then you have "glazed" plates, clean each plate with 600 grit sandpaper and reassemble...get a new clutch spring assembly (weakened spring causes "shudder", slippage, and consequently glazing). Reassemble and adjust correctly (many forums out there with info).
3)Replace the full assembly and adjust correctly at setup. Adjust regularly....I check adjustment about every 300-500 miles.
4)Pay a shop to do these things for you.

You will find the main jet in the carby is the problem, i had a similar problem with a yz426, cleaned the carby out several times but the actual jet somehow was damaged and ran fine once replaced

Ok
2 things.Either the clutch is not adjust correctly or,
Some of the clutch plates have fused together.This is a common problem if a bike has sat around and not get used for a while.The clutch pack needs to be pulled apart,cleaned,and PUT BACK IN EXACTLY THE SAME ORDER as it was pulled apart.This part is critical.It is a usual thing with these models.It's not a big job.Just don't mix up any plates.I am pretty sure this will be your problem and I hope I helped you.

A quick solution is to tap on the carby float bowl, with something like a screwdriver handle. sounds like the needle and seat is stuck, sometimes a few taps on it can fix it. Your carby float is stuck down.
You may have to take the carby apart if the easy solution dosnt work.

Be sure the exhaust pipe is not partially plugged up with dirt. If not, remove the exhaust pipe and go for a quick ride down the street. If the power band is back, the pipe has an internal blockage. If not, then remove the carb and air filter for cleaning. If no luck then pull the head and run the piston to the bottom. Check the exhaust port for carbon build up. Clean out any build up with a screw driver, preferably from the exhaust side. Decarbon the head and the top of the piston and reassemble top end and exhaust pipe. If still no joy, the crank seals, (and possibly the crank bearings) probably need to be replaced.

The choke allows more fuel into the engine, I would say that you have dirt or bad gas stuck somewhere in your carb, so give it a good and thorough cleaning, including the pump. Also make sure your air filter is clean!

Just a thought, At first I would suspect low cicuit on carb being plugged or mixture passage. But after reading your cleaning carb I would be inclined to say check your timing as long as you are sure your carb is cleaned well and adjusted.

wr 200 front fork oil capasity

sounds like you have a clogged pilot jet. did you remove the jet and make sure it is clean by holding it up to the light? could you see through it? you mentioned that you cleaned the carbs, but if you didn't remove the jets and make sure they are clean, then more than likely your pilot jets are clogged.