http://tech.nsr-world.com/nsr250/all-nsr250/nsr250-stock-carb-settings.php
Your situation is a classic example of why we do not support jetting discussion, as the state of tune is unknown, and anyone stumbling onto this thread via a basic internet search with similar symptoms and little NSR/2-stroke/problem solving knowledge, may blindly copy settings.
I'm past caring what some people think of this policy, as I can't be arsed with being threatened with legal action over it again, so please don't waste your time questioning it.
If you're lucky, it's just a spark plug that's breaking down. Seen plenty of plugs that spark outside of the combustion chamber, that clearly aren't doing their thing once under compression. I've seen BR9ECMs (and R5300As) that just refuse to work properly after getting wet/flooded too.
Personally I would do a compression test on each cylinder. It's very possible to lightly damage a piston and barely mark the nikasil bore. Looking up the exhaust only shows half the story. Maybe pop the carbs off too, and look down the inlets at the other side of each piston. You may even have caught a ring on the corner of a port. Plenty of things you can't see, just by looking up the exhaust, I'm afraid.
I hope it's just something simple, like a plug.
_________________
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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