In a meeting held yesterday at Valencia, the Superbike Commission, unanimously approved the following proposal concerning the restrictors for 1000cc Superbike machines, for the 2004 season.

The engines must be fitted with restrictors as follows:

2-cylinder: 50 millimetres3-cylinder: 39 millimetres5-cylinder: 27 millimetres6-cylinder: 22.5 millimetres

All the other specifications concerning the restrictors (Art. 2.4.4.1 of the Road Racing World Championship Regulations for Superbike) remain the same.

For 4 cylinder 1000cc engines, the restrictor rule of 32.5 millimetres has already been enforced for the 2003 season.

The sizing shown above shows that two-cylinder engines [such as Ducati's V-Twin] will still be competitive against the three [Foggy Petronas] and four cylinders [Suzuki, Honda etc] due to the significantly larger engine intakes.

However, should one engine configuration prove to be dominating, it is likely the rule would be revised to ensure competition.