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'05 crf250r rattle/chatter in upper engine

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I recently purchased an '05 CRF250R for my son. The bike ran when we looked at it but two weeks later went and picked it up, it wouldn't run once we got it home. Pulled and cleaned the carb and found the float valve stuck closed. Once I started it, it had a rattle in the upper engine, like under the valve cover. Pulled valve clearances and re-shimmed exhaust valves and re-assembled. Rattle is still there. Checked the tensioner on timing chain and it is putting good tension on chain. Any ideas???

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It's probably the decompression pin which is totally normal. Once the RPM's are raised, the noise should go away.

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Thanks. Didn't think about the cam bearings but still have it semi-apart. Will check. Thanks also for the crfsonly site too.

Charlie i saw what I think you are talking about, spring loaded on the end of the cam? What is the purpose of it?

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Thanks. Didn't think about the cam bearings but still have it semi-apart. Will check. Thanks also for the crfsonly site too.

Charlie i saw what I think you are talking about, spring loaded on the end of the cam? What is the purpose of it?

It kicks the exhaust valves open just a tad to allow you to kick start it. If it wasn't there, you wouldn't be able to kick it bacause the compression would be too great.

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Hats off to you Charlie C, decompression lever- raised rpm's. Then decided to look at my hot-start lever that quit working. It was hung up in the carb and while trying to free it up, broke it off in the carb. :/ Managed to get it out, now waiting on new one to arrive.

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Hats off to you Charlie C, decompression lever- raised rpm's. Then decided to look at my hot-start lever that quit working. It was hung up in the carb and while trying to free it up, broke it off in the carb. :/ Managed to get it out, now waiting on new one to arrive.

On the hotstart lever, I thought all you did was change out the clutch lever and it was working fine prior to doing that. My kid always overtightened the bolt that holds the lever in and it would hang up like the issue I thought you were having. That's why it's nice to get feedback from others! Some of the answeres are so outlandish and others try to beat that person down. Correcting them is one thing, but making them look like an idiot is just wrong and you have that on here unfortunately from time to time. I stay clear of the CRF450r threads for that reason. It's mostly guys waiting for someone to make a mistake on an answer so they could beat them into the ground. Pretty sad IMO!

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On the hotstart lever, I thought all you did was change out the clutch lever and it was working fine prior to doing that. My kid always overtightened the bolt that holds the lever in and it would hang up like the issue I thought you were having. That's why it's nice to get feedback from others! Some of the answeres are so outlandish and others try to beat that person down. Correcting them is one thing, but making them look like an idiot is just wrong and you have that on here unfortunately from time to time. I stay clear of the CRF450r threads for that reason. It's mostly guys waiting for someone to make a mistake on an answer so they could beat them into the ground. Pretty sad IMO!

No sir, I hadn't done anything to the hotstart prior to this. Looks like you may have been thinking of someone else. But your idea on the decomp lever was on que- raised the rpm's and noise was gone.

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