It all depends on the port timing. A stock NSR shoudl be around 120psi though.

However Ive tested RS250's which have made almost 80bhp with as little as 45psi! This isnt due to worn rings, just the fact the exhaust ports are so high that the volume of air above it is so small they give a very low compression reading. Of course once the engine is spinning the hight exhaust port comes into its own giving better peak power.
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If I have to take the carbs off once more...