From a press release issued by series organizers:

The following is a list of the provisional rule changes for 2003. While this may not be the final version, any further changes are expected to be minimal.

The FIM will release the final set of rules in the near future.


2.8.39 Four stroke engines

1. Motorcycles engines of mass production only, with a Stocksport homologation.
2. Maximum capacity: 1005 cc.
3. 4 cylinders maximum
4. The original crankcase and cylinders may be modified, but stroke and bore must remain as originally produced by the manufacturer.
5. Crankshaft and flywheel must be original. Balancing and polishing is allowed. Welding is not allowed. The minimum weight must be 95% of the original part.
6. Connecting rods may be altered or changed. The length must remain as original. The material must be of similar alloy as homologated. The minimum weight of a modified or replaced connecting rod must be 95% of the original part.
7. Pistons, piston rings and piston pins may be altered or replaced, but the bore must remain as homologated.
8. The original cylinder head may be modified, welding is allowed only in case of repair (this means that it is not allowed to have each cylinder welded in the same positions). The number of ports, valves, the diameter of the valves must remain as originally produced by the manufacturer.
9. Valves, valve springs and valve spring retainers may be altered or replaced, but valve and valve spring material must remain the same.
10. Carburettors may be altered or replaced. Fuel injection is free and can be replaced by carburettors.
11. Camshaft may be altered or replaced.
12. The cam drive method must remain as originally produced by the manufacturer.
13. Cam sprockets can be modified or replaced.
14. The ignition/engine control system is free.
15. The gear ratios are free. The maximum number of gears must remain as originally produced by the manufacturer.
16. The clutch system type must remain as originally produced by the manufacturer. Clutch springs, plates and basket may be altered or replaced.
17. The generator may be removed
18. Electric starter must be in place and work. The engine must start on the grid with the electric starter for the warm up lap before the start of the race.
19. The use of exotic materials such as ceramics, metal matrix or aluminium beryllium is not allowed.
20. Oil lubrication system is free.

For 2003 only
Engines which have been introduced on the public market 1995 or before: Max capacity 1100cc. Bore and stroke must remain as originally produced by the manufacturer. In all other points they may be modified according to the rules of 2002.

Air box 2.8.xx
An air box must be used.

The air box must completely closed around the induction. Bell mouths, the carburettors or throttle bodies may be entirely with in the air box.

The engine must have a closed breather system. The engine breather must be connected and discharge in the air box.

The air box must be constructed in such a way as to prevent any oil discharged in the air box from spilling on the track. This oil containment must hold a minimum of 1000 cc of oil.
The air box must be sealed to prevent any spillage of oil or fuel.

The inlet into the air box from the air ducts or open air must be above the lowest point of the bell mouth lips.


2.3.5 Wheel Rims and Tyres
The front wheel rim width must be 9″ maximum.
The rear and side tyres rim width must be maximum 11″.

2.8.16
Delete the sentence regarding the fixing points of side to main body.

2.8.25
2) Side and rear tyres must not exceed 254 mm measured like at point 1)

2.8.xy
The use of traction control system is not allowed

2.8.xz
The use of non passive suspensions is forbidden.

2.8.20.3
Modify: ” The ignition cut out must be placed as near to the centre of the handlebar as possible and must be operated by a non-elastic string of adequate length and thickness and strapped to the driver’s body………”

Noise
Max. 105 db/A measured at 5500 rpm