2004 Superbike Rules

From a press release issued by AMA Pro Racing:


Preliminary Support Class Rules Also Announced

PICKERINGTON, Ohio (Aug. 18, 2003) -- The AMA Pro Racing Board of Directors has ratified technical rules for the 2004 AMA Superbike Championship season and approved a preliminary set of rules for support classes including Supersport, Superstock and Formula Xtreme. A refinement to the 2004 class structure has also been approved. An overview of the rules changes can be viewed at www.USSuperbike.com.

Scott Hollingsworth, AMA Pro Racing CEO is confident the new technical rules will help achieve the objectives of continuing to deliver close competition and quality entertainment, maintaining adequate control of costs, and encouraging increased participation from major motorcycle manufacturers. “With the input of all major stakeholders, we have created a set of rules that will provide the ideal marketing platform for continued growth,” said Hollingsworth. “The United States represents the world’s most important motorcycle market and we’ve opened up the door for more companies to use motorcycle racing as a means to promote their products.”

Development of the final AMA Superbike rules included measures taken to improve parity among the two primary engine configurations. “Keeping the twins competitive and opening the door for increased manufacturer participation was a primary goal for 2004,” said Hollingsworth. “We expect performance of the next generation multi-cylinder models to advance even further and it’s imperative that we adjust the rules structure to account for this ongoing development. We have created an environment that provides opportunity for all manufacturers to showcase their products and remain legitimately competitive.”

In addition to finalizing the 2004 AMA Superbike rules, the AMA Pro Racing Board of Directors has approved a preliminary set of rules for support classes. AMA Pro Racing licensed riders and credential holders may comment on proposed support class rule changes during a 30-day comment period beginning Monday, Aug. 18 through Tuesday, Sept. 16. Comments can be made on AMA Pro Racing’s RIDERS ONLY website at www.amaproracing.com/ridersonly. After the 30-day comment period concludes, AMA Pro Racing will review suggestions before sending the package to the AMA Pro Racing Board of Directors for final ratification.

Hollingsworth confirmed that the 30-day comment period, specifically for support classes, will yield final technical rules for AMA-sanctioned road racing in the United States. “With AMA Superbike complete, we can now turn our attention to the support classes,” concluded Hollingsworth. “At the end of the process, we’ll have created a class structure and set of technical rules that best serves the needs of the entire racing community, including our fans, and allows for continued growth and commercial development of our series.”

Summary Of Superbike Rules Changes For 2004:

The following technical categories indicate the level of modifications permitted effective January 1, 2004. Actual 2004 rule book language will be posted on www.amaproracing.com at a later date.

Fuel injection throttle bodies:

Multi-cylinders – Restricted to stock throttle bodies and air intake boxes.

Twin-cylinders – In addition to the stock throttle bodies, one alternate, AMA-approved throttle body type/set is permitted as well as aftermarket air intake boxes.

Engine modifications:

Multi-cylinders – Limited modifications are permitted but such items as stock camshaft lift, stock valve sizes and lightly-modified stock crankshafts are required.

Twin-cylinders – The same limited modifications as multi-cylinders are permitted except for the following items:

Valve sizes and material are unrestricted.
Camshafts are unrestricted.


Multi-cylinders – In addition to the stock set of gear ratios, one alternate, AMA-approved set of ratios is permitted. Primary drive ratios must remain stock.

Twin-cylinders – The same rules as multi cylinders apply.


Multi-cylinders – Limited modifications to the stock frame are permitted such as gusseting for additional strength.

Twin-cylinders – The same rules as multi-cylinders apply.

Minimum weight:

Multi-cylinders – The minimum total motorcycle weight (less fuel) is 370 lbs.

Twin-cylinders – The same 370 lbs. minimum weight applies.

Summary of proposed changes to 2004 Support-class rules:

The following rules changes were created utilizing input from AMA Pro Racing staff, AMA Pro Racing Road Race Advisory Board, AMA Pro Racing Board of Directors, participating teams and riders. The changes cover general technical aspects of Superstock and Formula Xtreme which are support classes in the AMA Chevy Trucks U.S. Superbike Championship.

As an AMA Pro Racing competitor or credential holder, you have the opportunity to express your opinions and offer suggestions regarding these proposals.

This comment period starts Monday, August 18 and ends Tuesday, September 16, 2003.

When submitting comments, please reference the proposal number and state your remarks and suggestions as briefly as possible. If you are sending your response by mail, use the following address: AMA Pro Racing - Rules Comment, 13515 Yarmouth Drive, Pickerington, OH 43147.

If you would like to fax your comments, please send to: AMA Pro Racing - Rules Comment, (614) 856-1924.

We appreciate your input and we hope that you will take this opportunity to provide feedback concerning these road racing proposals. Following a review of comments submitted and final approval of the AMA Pro Racing Board of Directors, the rule changes will become effective January 1, 2004.

04-1RR. Superstock

Superstock technical regulations are unchanged with the following exceptions:

1. Engine Displacements: The displacement range is changed to 745cc-1000cc for all motorcycles. Single-cylinder motorcycles are not eligible. 1350cc air-cooled twins are not eligible. All eligible motorcycles must be homologated (AMA Pro Racing approved) per the current Superstock procedure.

2. Tires: Slick racing tires are required on all motorcycles in dry track conditions.

3. Entry Restrictions: Riders who are employed or contracted by the manufacturers as team members in Superbike are restricted from entering Superstock.

04-2RR. Formula Xtreme

1. Engine Displacements: The displacement range for multi-cylinder four-stroke motorcycles is reduced to 450cc-600cc. The range for twin-cylinder four-stroke motorcycles is 595cc-750cc. 1000cc-1350cc air-cooled twins are permitted. Single-cylinder motorcycles are ineligible. Two-stroke motorcycles are also ineligible. All eligible motorcycles must be homologated.

2. Engine Modifications: Allowable engine modifications for all Formula Xtreme motorcycles are the same as the 2004 multi-cylinder Superbike rules with the following exceptions:

Engine modifications to 1000cc-1350cc air-cooled twins are unrestricted.

Stock throttle-body assemblies and air boxes are required on all motorcycles except 1000cc-1350cc air-cooled twins.

3. Chassis/Frame Modifications: Allowable chassis/frame modifications for all Formula Xtreme motorcycles are the same as the 2004 Superbike rules with the following exceptions:

Chassis/frame modifications on 1000cc-1350cc air-cooled twins are unrestricted.

OEM swingarms must be utilized with limited modifications (gusseting, stand brackets, etc.). 1000cc-1350cc air-cooled twins are unrestricted.

4. Bodywork: Fairings, seats, fenders and side panels may be modified or changed to any aftermarket or custom type as long as "fluid retention" regulations and general equipment standards are adhered to. Stock fuel tanks with limited modifications (fuel filler, fuel valves, etc.) are required on all motorcycles except 1000cc-1350cc air-cooled twins.

5. Weight: Minimum weight limit (TBD) applies to all motorcycles.

6. Entry Restrictions: Motorcycles entered in Supersport may not be entered in Formula Xtreme.
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