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what is missing and-or broken

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Hi everyone. I recently got myself a 250 to hit some trails. Today I noticed this hole and looks like some sort of seal is missing or broken in the centre. what is this? what do I need to sort this? when I run the bike smoke comes out. Not loads but it is visible.. thanks.

20170415_130534.jpg

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Um, yup, that's a problem.

I'm not so brilliant as to believe I can identify that motor from just that pic, but I'm thinking YZ?

What you're looking at is what appears to be the pivot point for your power valve. It may not be the pivot exactly, but it's power valve-related. And if it's open through to the cylinder, it's gonna cause a massive air leak. This, in turn, will cause a massive lean condition, which will lead to a massive meltdown of your top end. FIX IT NOW!

Now, just to avoid being labeled an idiot, I suppose your motor's architecture might be such that an opening in that spot won't allow unintended air into the cylinder and it's not going to cause a lean condition. I'd have to actually look at it, and not a picture of it, to be sure. But a good rule-of-thumb is any unintended opening that allows air into or smoke out of your engine is a really bad idea. Being a 2-stroke only makes such air leaks 100 times worse than were it a 4-stroke. Don't read that as a 4-stroke bias, I'm a dedicated 2-smoke guy. But I think you really need to fix that before starting the bike again.

"No Sniveling"
And:
"You really should have known"

No, I'm not being a Richard, I'm quoting genius...

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56 minutes ago, -AC- said:

Um, yup, that's a problem.

I'm not so brilliant as to believe I can identify that motor from just that pic, but I'm thinking YZ?

What you're looking at is what appears to be the pivot point for your power valve. It may not be the pivot exactly, but it's power valve-related. And if it's open through to the cylinder, it's gonna cause a massive air leak. This, in turn, will cause a massive lean condition, which will lead to a massive meltdown of your top end. FIX IT NOW!

Now, just to avoid being labeled an idiot, I suppose your motor's architecture might be such that an opening in that spot won't allow unintended air into the cylinder and it's not going to cause a lean condition. I'd have to actually look at it, and not a picture of it, to be sure. But a good rule-of-thumb is any unintended opening that allows air into or smoke out of your engine is a really bad idea. Being a 2-stroke only makes such air leaks 100 times worse than were it a 4-stroke. Don't read that as a 4-stroke bias, I'm a dedicated 2-smoke guy. But I think you really need to fix that before starting the bike again.

"No Sniveling"
And:
"You really should have known"

No, I'm not being a Richard, I'm quoting genius...

OK thanks. it  a yz. I'm no mechanic tho so what am I looking at to get this sorted. would sealing it be a temporary solution?

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12 minutes ago, molok said:

OK thanks. it  a yz. I'm no mechanic tho so what am I looking at to get this sorted. would sealing it be a temporary solution?

no that is where the vent hose is supposed to attach.

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1 minute ago, gedakbx said:

no that is where the vent hose is supposed to attach.

i see. so what's the damage in my pocket lol. is it an easy fix?

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1 minute ago, molok said:

i see. so what's the damage in my pocket lol. is it an easy fix?

No idea but that part cant cost that much

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4 minutes ago, gedakbx said:

No idea but that part cant cost that much

OK.  thanks for the help man. appreciated.

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The nipple broke off. It's just a vent. Rig a hose onto it and down to the frame temporarily or spooge will litter the left side of your bike, maybe a brass nipple from a hardware store could work.

image.jpg

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Go on EBay bet you can find one cheap. Remember there are a lot of years that cross reference, 2002-2017 in most instances .

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99-17, left power valve breather cap and elbow

Probably get away with #44 for 6 bucks, or if you need #22 also it's another 21 bucks. 

IMG_6015.thumb.PNG.e7d61bd7beea9b626a859b2cc640f728.PNG

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Excuse my KTM-based Yama-ignorance. Not used to seeing a power valve vent, and I panicked. Ignore me...

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8 hours ago, dirtbikesonny said:

Go on EBay bet you can find one cheap. Remember there are a lot of years that cross reference, 2002-2017 in most instances .

thanks m8. it's a 2002

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2 hours ago, Gary YZDOC said:

99-17, left power valve breather cap and elbow

Probably get away with #44 for 6 bucks, or if you need #22 also it's another 21 bucks. 

IMG_6015.thumb.PNG.e7d61bd7beea9b626a859b2cc640f728.PNG

thanks for that diagram. what is 47.. I don't think I see it on bike... getting worried..

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7 minutes ago, Snider said:

02 PV vent

 

vent_zpssfskoddj.jpg

where does it lead to tho...from there.. sorry never seen this b4.

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just remove the two screws and it pulls out like a plug.. it's basically a drain for the power valve housing. so there will be some oil built up that will drain out.. no need to replace the oil that drains.

Edited by Snider

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1 minute ago, Snider said:

just remove the two screws and it pulls out like a plug

the rubber hose-pipe. I honestly can't see that anywhere. where does the rubber lead to ?

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Just now, Snider said:

it just dumps on the ground..

 

vent%20hose_zpsmwwxxfsm.jpg

I see.  thanks man for the pics. so it's not a engine killing scenario... il get on it. thanks again man.

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