The inevitable has happened – no more smelly, smoky, and screaming two-stroke-engined bikes competing in any of the three MOTOGP classes in 2012. We will surely miss them but times are changing and a brand new 250 cc four-stroke class will replace the previous entry level 125 cc two-strokes.
The full regulation document can be found on FIM’s official website but below are some interesting powetrain-related regulations:
Engine Specifications
• Four-stroke, single cylinder with maximum capacity of 250 cc;
• Maximum bore size 81 mm with oval pistons not allowed;
• Naturally aspirated only (turbo/supercharging not allowed);
• Maximum crank speed 14 000 r/min;
• Pneumatic or hydraulic valves not allowed;
• Maximum engine cost is limited 12 000 euro;
• An official engine-control unit (ECU) must be used by all teams;
• Variable inlets and exhaust tracks not permitted;
• No moving parts in the exhaust;
• Only one throttle that is mechanically controlled by the rider (i.e. throttle cable);
• Fuel injectors (maximum two) must be located upstream of the intake valves (no direct injection);
• Fuel pressure maximum of 5,0 bar;
• Expected power: approximately 36 kW.
It is clear from the above list that the main focus of the regulations is to keep costs down. Secondly, no fancy electronic engine-control will be allowed which should give the rider absolute control over the power delivery without the help of engine-management aids. This promises to allow rider talent to shine through in a highly competitive field. The power figure of 36 kW does not sound much but with a bike and rider weighing only 148 kg it should provide some interesting racing!
