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Autodecompression and loose exhaust valve

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I’m putting this out there in case it’s ever of help to someone.  Last year I rebuilt my 1997 XR 250 as a 277 with a kibblewhite valve train.  Fired her up and noticed the kibblewhites were louder than stock and kicking was much more difficult.  I thought it was just the extra compression and the bike ran great.  I just used the handlebar mounted release and rode it fine. 

Parked it for a while and started riding it again this year, and the valve noise just seemed too loud.  But the bike only had a few hours on the rebuild, how could it be out of spec?  And wouldn’t they get tighter usually anyway?

Lo and behold upon inspection, the right side exhaust valve was super loose.  I must have skipped it somehow on reassembly.

Now the valve train is much quieter and the bike is much easier to kick.  I’m pretty sure the valve was so loose the auto decompressor was not engaging.

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21 hours ago, Jack the Dogg said:

I lost the auto decomp when I switched cams. Don't miss it AT ALL. Just one more thing to go wrong.

Rode today and frankly I find the bike easier to kickstart without the auto decompression because it’s easier to find TDC.  But it’s still easy and now bump starting is easier too.  I could go either way if just ride experience is the question. I think I’d rather not have it for reliability sake but I also don’t worry about it either.

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I like the kicker auto decompression release because it make restarts on the trail so much easier.  The manual also makes bump restarts easier.

The best is the auto centrifugal compression release on my CRF250X that works so good there is no need for a handle bar lever and less braking stalls of the engine, and easier bump starts if you do brake stall the engine.

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