YZ250 Two Stroke Power Valve Rebuild

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Latest on our YZ250 build where we breakdown the process of two stroke power valve rebuild. These Yamaha two stroke have a pretty similar power valve for a lot of years and we break down he entire process from start to finish.
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• Racer X Films: 2001 Ya...
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• YZ250 Tire & Wheel/Tir...
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#yamaha #yz250 #yz

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16 июл 2024

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Комментарии : 44

@seamarsh3756 Год назад

Can you post these with no music all the way through, no fast forward, would be far superior:)

@kirbylee57 Год назад

Why did you speed up the video? Wanted to learn something here.

@3BrothersExtreme 2 года назад

Brad always makes it look so easy!

@chriscardoza9785 2 года назад

Very interesting to see how you guys do All that awesome stuff to the yz 250..

@TheCarlejoseph 2 года назад

Great video! Thanks for the tips.

@kirbylee57 Год назад

what tip did he give? Help me out.

@EarthSurferUSA 5 месяцев назад

Well, I cleaned the goop out of the hex heads, used a new allen wrench (good one too), and stripped the head out of the center power valve shaft screw. That one was too tight for the head. Had to drill the head off, drill a smaller hole and use an easy-out. Those are some soft screws. I will replace them with better ones.

@xXShadowProductions1 2 года назад

Thank you for the tutorial , however at 9:35 the gasket is facing the wrong way, as the notch is supposed to look down not up. Not sure how much of an issue it actually is, but I figured I`d say something since the notch probably has a reason to be there.

@erichildreth7562 2 года назад

I just put a new cylinder on my YZ250 and I double checked my manual. On page 4-19 it shows this notch "down" in the diagram.

@2008yam 2 года назад

Correct it’s down.

@mc9304 Год назад

This comment scared me - I had paused the video when the cover came off and saw it down. Reassembled my bike then watched to rest and heard him say it went up! Thanks for clarifying via the manual

@EarthSurferUSA 5 месяцев назад

You are right, he is wrong. My cover is off, gasket stayed on the cover, Gasket notch is down, and it is for clearance for the center valve shaft bolt head. Not too many people can do a perfect How to vid.

@GForceRacing543 Год назад

The v notch on the power valve gasket is actually supposed to be on the bottom. But yeah..

@GNX157 6 месяцев назад

Buy that man a 30L professional ultrasonic cleaner.

@travisgiltrow7804 2 года назад

10/10 sweet video

@chriscardoza9785 2 года назад

You make it look so easy.and l was wondering do you have to time the power valve at all on this model...

@brianpolen1087 2 года назад

Nice job. I know we all think we're tough guys, but when you use contact cleaner like that (esp. over the years), you should put on some nitrile gloves.

@EarthSurferUSA 5 месяцев назад

Tough guys or baby sitters, take your pick.

@vicenteroman5754 Год назад

Hi i have yz250 i saw smoke come out for the breather house it is normal?

@mikebrown41182 2 года назад

Is there much friction in the powervalves, stress?

@motoadventurehaiti 2 года назад

Are there seals inside the area where arm connects to the side with the screw? Above the coolant drain. My bikes just dumping bunches of oil after it sits for a while out of that cover.

@dirtbiketv1 2 года назад

Email Jay directly with any questions. Contact info in About tab.

@johncashen2170 9 месяцев назад

Where may I obtain the cylinder hone you used ?

@dirtbiketv1 9 месяцев назад

Email Jay. Contact info in About tab.

@chriscardoza9785 2 года назад

Just wondering can you use carb cleaner or is that a bad idea!

@dirtbiketv1 2 года назад

Email Jay directly with any questions. Contact info in About tab.

@michaelanderson1727 2 года назад

I stripped the phillips head screw that goes to the keeper on the right side. Any ideas to get it out? I already tried an EZ out and it sheared. Oh lord im in over my head!

@SheriffBo 2 года назад

Heat is your friend.

@Ares4c Год назад

Bro my Yz 250 2t 2019 are leakin very much oil in the powervalve , i change the seals and nothing. How i can repare This? Help

@dirtbiketv1 Год назад

email and send pictures--

@EarthSurferUSA 5 месяцев назад

The carb is jetted rich from the factory. Learn how to jet your carb, and you will get more power, and virtually no ugly oil mess. Usually, dropping the needle one notch (if your spark plug is black). leans up the middle very well, but can be a big jump. You can get little washers that go under the needle clip to go less than a full needle groove jump. Then I do wide open run to test the main jet, and put in a leaner main jet if needed until the plug is a light color brown at full throttle. (Hit the kill switch at full throttle so the plug does not darken up for a false plug reading from lower rpm running.). You plug should be a light brown color on the porcelain (and everything else dry)

@SpitSatan666 Год назад

name of the assembly music?😅

@jeremymullen5378 2 года назад

🔥👊🔥🏍🏍🏍

@leelafarlett3535 6 месяцев назад

Looks like all you gotta do get it a "little bit clean" so you can get the "doo dads out". then take that stuff on the side off take and " important stuff" apart , pitch them in a pile, clean em up, and stick it all back together, and thats it! I think i'll look for another video, hopefully without loud grunge music. Too fast for me.

@barkeep25 2 года назад

Some of the material has scuffed away on my powervalve assembly. He was talking about blowby, how do you know when to replace that?

@dirtbiketv1 2 года назад

Email Jay directly with any questions. Contact info in About tab.

@EarthSurferUSA 5 месяцев назад

If it operates smoothly it is probably fine. Exhaust gas blows by the valve even when new. It is not designed to hold gases like piston rings are, and the power stroke is done as soon as the exhaust port opens up. All that brunt exhaust oil under the first cover he took off is from the exhaust gases going by that valve a bit during what is called "the blow down phase". You won't lose any power unless the valve starts hanging up.

@matthewlidel4324 Год назад

Is it normal for oil to drip out of the power valve vent line.?

@azff Год назад

@Matthew Yes, it's normal for the oil to drip out of the power valve hose.

@EarthSurferUSA 5 месяцев назад

@@azff Stock bikes (with carbs), are jetted rich from the factory. If he jets the carb well, he will not only gain about 2hp, but most if not all of the exhaust mess we get will be burnt in combustion and then the drips dry up. My YZ (2019) was so rich, oil coming out of the silencer ruined 2 of my jerseys, ( oil spots won't come out). Liquid droplets are fling out of the silencer. Now that is "rich". :)

@azff 5 месяцев назад

@@EarthSurferUSA I've got a 2023 Yamaha YZ250. I bought it brand new and just as your experience it was super rich out of the box. I bought a JD kit and re-jetted for my elevation (1,200 ft) and it's running great. Still getting some (not much) oil discharge out of the PV overflow hose.

@RideWithTheWolf Год назад

Why would the power valve be hitting the piston rings? Or why would the rings be hitting the power valve?

@dirtbiketv1 Год назад

Email Jay. Contact info in About tab.

@EarthSurferUSA 5 месяцев назад

Broken valve parts, or somebody over bored the cylinder possibly, (which would need to be re-plated and use an oversize piston), and did not modify the end of the valve.