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couple 02 yz125 top end questions...

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went riding sunday, bike was runnin good. 410 main, 2nd needle clip (needle pro circuit recommends) 32.5 pilot, in between 1 1/2 2 1/2 on screw(weather dependent). where i was riding when i got off the trail had maybe 1/2 mile of road to get back to the truck, topped the bike out had to back off the throttle a couple times so it didnt blow up. as soon as i got back and shut the bike off it was smoking a greyish color pretty bad out the exhaust, smelled like burning metal. as i was loading the bike up a guy came over to see what was goin on. he said it was my exhaust packing from the smell it gave off. what does burning packing smell like? also i took the pipe off to take a look.

1 the end of the exhaust packing, does it look burnt?

IMG_6782.jpg

how worn does my powervalves look?

IMG_6974.jpg

getting to much blow by?

IMG_7014.jpg

to many questions, i know.

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I'd be more concerned about the scuffing all over your piston than the power valve. You would have to take the valve out and do a proper inspection to know for sure.

It may be just the cam angle but it looks like you have been sucking dirt or a lack of lube.

If you spend a lot of time putting around and doing tight work then get out on the open stuff and really start "rippen it" then you most likely just smelled the pre-mix that has accumulated while putting around getting cleaned out. You arent going to "burn" your packing, you are just getting it hot enough in the exhaust system to make the oil residue smoke.

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Does the scoffing look bad? I'm getting a base gasket after work to open it up. What should I look for when I take the cylinder off

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You want to look for damage like deep scuffs big enough to catch your finger nail on. Imbedded "fragments" of objects stuck in the Nikisil. If the piston is scuffed as bad as the pick you will need a new piston and rings at the minimum. If the Nikisil is ok you can just have a shop run a hone on it and reuse the cylinder.

Use a can of carb cleaner and clean eveything up real good and post some pics...

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Like previously stated it was probably just the premix burning out of your packing. Out in the dezert one time me and my buddy ran hard completely topped out across a long lake bed. When we got back in the inside of my buddies silencer was glowing red and smoking like crazy. I don't know why his bike won't just blow up...

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I don't know why his bike won't just blow up...

lol do you want it to?

:busted: :busted:

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It wasn't premix the smoke was grey with no blue in it. I checked the cylinder walls and piston the marks didn't catch a fingernail one did and it was very little. My compression is normal also

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lol do you want it to?

:busted: :busted:

Actually I do. It's a 02 CR 250 and he's had it since 02. It's still on the stock piston and it absolutely rips. It must have hundreds of hours on it. Makes no sense to me!

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If your posting about stupid shit and arnt helping this thread why are you posting at all

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