From what I have read they changed the fuel injection, made over 170 changes to the engine including 10% more HP and 12% more torque.
Still, many articles state the torque is great for canyon, spirited riding and city but out on the open road underpowered.
I don't rip it up anymore. Did that on the Hayabusa. Lucky to be alive.
It's not for everyone but at 436 pounds wet it should be fun. At least for me. Still hard to find any info on the 2012 model. Everything is still 2011 specs. All sold from what I hear.
The 2012 motor has single Y intake and one throttle body. Black heads instead of polished.
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