In 2012, the all-new Moto3 class will replace the 125cc MotoGP class, which will be limited to a single-cylinder 250cc four-stroke engine.
Not many tests are reaching public eyes, but Honda Racing Corporation has releasing some footage of their tests with the NRS250 (Next Racing Standard) at a Japanese test circuit. This YouTube video shows the NR250 bike in action.
With the move to Moto3, there will be no more two-stroke World Championship races. The 2012 season will see four-stroke machines across MotoGP, Moto2 and Moto3.
As for specs, the 250cc motors in Moto3 will have a maximum bore of 81 mm. Each engine should last for three races minimum and cost not more than €12000 ($18,500 USD). Also, each chassis manufacturer if required should be ready to supply a minimum of 15 riders.
In 2012, Moto3 will join Moto2, which debuted this year. In Moto2, 600cc 4-stroke Honda spec engines replaced the 250cc two-stroke race bikes.