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Why is my decompressor system missing?

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I bought a 2002 XR400 with a broken intermediate shaft and I discovered that the decompressor system that should be on the camshaft is missing. It looks as though someone removed it and spot welded the holes where it used to be. I thought this was a completely stock bike until I saw this. I have everything back together except for the valve cover. Why would someone do this? Will I be able to start the bike without it? Should I put it back together as is or save and buy a new cam. I am really nervous about this motor now. Any help would be appreciated.

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Its fine. None of the aftermarket cams use the autodecompressor. Sometimes the decompressor breaks and has to be removed, or the previous owner just didnt like it.

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Will the little spot welds cause any problem with balance. Also, there is a little noticable wear on the cam journal in the middle. Is that common, beacuse there is no bearing to stop metal to metal contact.

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A little wear on the journals is pretty normal, It's kind of your discretion as to when it get to be serious. If it doesn't look too bad it probably isn't.

I don't know whether or not the welds would cause any trouble, maybe someone else can speak up on that:excuseme:

And like 'XR250rDr' said, most, if not all aftermarket cams get rid of the auto decompressor, but, correct me if I'm wrong, they also change the lift and duration of the cam to compensate for this.

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A camshaft is far from balanced to begin with, two spot welds arent going to affect anything. And the center journal does wear some, but probably fine just as long as it isnt galled.

...but, correct me if I'm wrong, they also change the lift and duration of the cam to compensate for this.
They just change the duration and lift to make more power. :thumbsup:

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I've got a complete stock camshaft with all that decompression garb on it if you need it P.M. me and you can pay for shipping. It is not necessary to have it on there.

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