sprocket ??

after the nut came off the 1000 I noticed the splines on the back side , installed, had been taperd, I assume because of the nut coming off, the question is, is there a problem with flipping it around to make sure the spline contact is better?

Wouldn't the offset be different?

it looks flat without any shoulder on either side

As long as it's not worn very much. As a chain stretches it wears the sprocket, shanging the shape of the curve where the roller fits in. If you flip it over the wear will be in the opposite direction. I'm not sure what symptoms you will experience, but I can't help but think that this would not be a happy relationship. At the very least you would probably experience excellerated wear on both the chain and the sprocket. Since front sprockets aren't terribly expensive, and since You already have it apart, I'd advise springing for a new one.
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