2011 Aprilia RS4 125 - it's 4-stroke!

Unlike what Kennon posted, no, this 125 single is not minarelli based. Both Aprilia and Derbi are under the Piaggio umbrella remember? The motor is a Piaggio, you can even see their logo in the cylinder casting. It is also *not bloody likely* that snipping a wire will net you any power like it would on a rev restricted scooter. This bike, unlike it's Derbi brother, is EFI with a Magneti Marelli MIU ECM and already spins to over 10000 RPM, there won't be any wire snipping going on. Beleive you me, I too am sad we're not getting an emissions-compliant 125 purejet 2 stroke, but we have to accept the fact that Piaggio doesn't seem to want that system in anything other than 50's and that BRP are gonna keep their grubby hands on their incredible ETEC. The 2 stroke is going away and all who could save it are sitting idle, so stop torturing yourselves comparing the RS4 with the RS125, this is a CBR125/YZFR125 fighter, and with more HP and less weight than either of those, it should do well.

I'm a fan of your work. A 450 twin in this would be awsome!