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How an you tell if a valve is bent?

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I have an xr200 and was told that one of the valves were bent. I took the bike appart to see for myself and i dont see where they mean this. How can u tell if it is bent? How do i check the valve spacing? The bike did quit running and i was told because the valves were so out of wack they bent. thanks

ovid

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So its not going? If the compression is real bad its probably the valves, if the valves were bent they wouldn't seal properly, I guess you would have to pull the head off the check properly.

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Sound as if you valve timing is off. If you do have a bent valve, you will have a lose of compression.

I'm not sure how far you went, when you took the motor apart, but you will have to pull the head off to actually see the valve faces. A tell tale sign will be marks on the top of the piston, were the valves will get hit by the piston.

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Hey sidekick. There are two marks on the piston where both valves hit the piston, it seems to me. Is that bad? Should the stock piston be flat? It looks like they should be there though, the marks i mean.

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What you are looking at are valve reliefs that are cut into the top of the piston and should be there. He means marks that show evidence of a hit. Valves DO NOT have to hit a piston to get bent. They can hit each other and get bent. Just a slight touch is all it takes. When they are hot and extended, they are very vulnerable. Doesn't sound like your problem to me if the bike was still running. Usually, they either stick after getting bent resulting in no compression. Check your static timing. Clint

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My friend pointed out to me that the intake valve was slightliy bent. There is also a shiny mark on the valve itself as if it did hit the piston. Its like a half circle. There is a little gap whre the valve sits on the head. That should be enough to cause a problem? I am gonna order a new valve and get to work on it. Gaskets maybe. That gasket looks real good. No marks on it. But they say to repalce right?

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The two mark are good inication the valve time was off. Any gap between the valve and the seat is not good. Always replace head gaskets.

Valve replacment is not that tough of a job if you have the right tools, mainly a valve spring compressor.

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Yea what i did is i put some water in the exhaust portion of the head. the water was tight and did not spill through the valve and the seat. I put water in through the intake and it gushed out the seat. ALready ordered it today . Good deal on ebay. Thanks for the time guys!

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