Not something I've ever personally seen on an NSR. They often smoke more on one cylinder when cold, even when in A1 condition though.

While not of any technical assistance, if the pump is properly adjusted and you are still concerned with its apparent irregular performance, I would suggest replacing it with a known good one. There are no serviceable parts in the oil pump.

Although it doesn't help your situation, I will say that while I have heard [very few] claims of dead NSR250 2T pumps, in my 25 years of NSR experience I've never personally seen one fail.
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Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

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