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oil sight glass and feeler gauge issues with my 08 yz250f

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This might sound like a retarded question but I just picked up an 08 YZ250f and first thing I went to do is check the valve clearances and how in the world do you get the feeler gauge under the middle intake. I just cut mine down to make it work but is there special feeler gauges for this. Second thing is I went to change the oil and filter warmed the bike up for a few min shut it off opened up all three drain bolts (pan,crank,and breather up top by skidplate) put everything back together with new filter filled it to top of sight glass started it shut it off topped it off looking at sight glass. And when I run it there's no oil in the sight glass when it shut it off it comes level but I only put half a liter of oil in and the manual calls for 1.15 that's why im confused any help would be great! And yes the bike is level on a stand

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This might sound like a retarded question but I just picked up an 08 YZ250f and first thing I went to do is check the valve clearances and how in the world do you get the feeler gauge under the middle intake.

No such thing as a stupid question, only stupid answers.

You have two options with middle intake;

Take a grinder to the one you have and narrow it enough to fit, as you have done (and add it to your 'custom tool' drawer in your tool box), or buy the Motion Pro feeler gages, they are narrow enough to fit.

The other thing you need to be aware of is the decompression pin on the left exhaust valve. If you are not careful, you may not be getting an accurate reading if the feeler gage gets between the pin and the bucket.

Second thing is I went to change the oil and filter warmed the bike up for a few min shut it off opened up all three drain bolts (pan,crank,and breather up top by skidplate) put everything back together with new filter filled it to top of sight glass started it shut it off topped it off looking at sight glass. And when I run it there's no oil in the sight glass when it shut it off it comes level but I only put half a liter of oil in and the manual calls for 1.15 that's why im confused any help would be great! And yes the bike is level on a stand

Yup, not a very thoughtfull design. Just measure the correct ammount of oil during the change and only use the sight glass to verify the engine has oil when it hasn't been running for a while (don't use the sight glass to adjust the oil level).

When the engine is running, all of the oil is stored in the tank in front of the engine. It is normal to not see any oil in the sight glass when running. It's also not going to show any oil in the sight glass untill the machine has been sitting for an hour or more after running.

After shutting the engine down, most of the oil remains in the tank and only after an extended period of time will oil show up in the sight galss as it leaks past the oil pump and back into the crancase. How long it takes the oil to show up in the sight glass is dependant on what the ambient temperature is, oil viscosity, age and wear of the engine, etc.

When you add the oil to the crancase after an oil change (and provided that you did drain all of the oil), disregard the sight glass and just add the required ammount listed in the manual.

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opened up all three drain bolts (pan,crank,and breather up top by skidplate)

You removed the vent screw on top of the tank, but did you remove the drain bolt on the bottom of the tank?

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Yeah there's two bolts to take out on the bottom one is directly under the motor and the other is on the side that's the one for the crank and I also took the small bolt out behind the front fender that's the vent right? And also took the fill cap off also to let it vent when draining. Thanks for the info ill just go by what the manual says and trust it I just wanted to make sure before I rode the bike good thing I asked!

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