CR5's been done, but not heard of a CR250 going in an NSR chassis.

I got good power out of my CR250 Super Retard, but it wasn't an NSR beater.

I think that you need to buy another CR250 motor and glue them together. That'd be worth a laugh.

A CR250 in a YSR chassis sounds like fun.

I loaded the CR250 engine into a CBR150 chassis, but I never really got around to finishing it all off. Then sold the CBR frame, so the 250 engine is still sitting in my workshop