Image shows stock NSR250 manifold on the left, and RS250 PJ38 carbs fitted to post 1991 RS250 inlet manifolds on the right.

RS250 Carbs

Image below shows the difference between the pre 1991 (90° motor) RS250 manifold that fits the NSR crankcase on the right, and the post 1991 (72° motor) RS250 manifold on the left.

RS Inlets

 

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