The 400 will have to be prototypes, its in the FIM rules. Remember the WCM/R1 cylinder head fiasco?

I also heard the as well as the Aprilia 450 rs combo, Kawasaki is working on a 450 but a parrallel twin. There are a few companys making some great 500 twins one called Maxsym, theres is making 90bhp and spins to 11k, size isnt an issue because they have been fitted to motarded YZ450 frames for testing.

As for boring power deliverys rubbish, ride a modern four stroke crosser, 12k with a kick, and just put a nasty camshaft in a r1 then you get your power band.

I have had 5 21's an rg500 and so on and like two strokes but if they can make a reliable (remeber factory warrenties!!) 450 or 500 twin thats small as an RS and has some mojo and meets emisions then great bring it on.
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