From my experience, the ZXR400 radiator is the biggest you will be able to get hold of easily. Many of the other 400's fitted them when they were tuned beyond their own rad abilities (friends FXR400 making 82hp for instance. Until I crashed it anyway...)

No idea how it'd mate up with an NSR, but that's half the fun isn't it?
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
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