Rules

1. Engines:        A. Any type two-stroke cycle engine or engines, no limit to modifications.        B. Any type four-stroke cycle engine or engines, no limit to modifications. 2. Minimum Weight / Maximum Displacement        A. Rotary valve or Reed valve Two-Stroke Cycle Engine or Engines, 230 lbs plus one pound for each cc or fraction of a cc. Multiple engines or cylinders are permissible. 210 cc maximum total displacement .        B. Flat Head Four-Stroke Cycle Engine or Engines, 190 lbs plus one pound for every 3cc or fraction of a cc. Multiple engines or cylinders are permissible. 466 cc maximum total displacement.        C. Piston Port, McCulloch or US820 (West Bend) Two-Stroke Cycle Engine or Engines, 170 pounds plus one pound for every cc or fraction of a cc. Multiple engines or cylinders are permissible. 210 cc maximum total displacement.        D. Overhead Cam (OHC) Four-Stroke Cycle Engine or Engines, 245 lbs plus one pound for every 2cc or fraction of a cc. Multiple engines or cylinders are permissible. 265cc maximum total displacement.        E. Overhead Valve Push Rod (OHV) Four-Stroke Cycle Engine or Engines, 220 lbs plus one pound for every 2.5 cc or fraction of a cc. Multiple engines or cylinders are permissible. 446cc maximum total displacement.        F. Forced Induction. If a kart is equipped with some type of supercharger or turbocharger, add 15 lbs for each cylinder that is served by the system.        G. Mixed Engine Type in Multiple Engine Situations. The minimum weight for the engine corresponding with the higher weight will be imposed.        H. Fuel. Gas or Alcohol. Oil may be added but no performan enhancing additives.        I. Driver must be 16 years of age to compete        J. No transmissions allowed 3. Calculating Displacement / Declaring Weight.        A. The bore will be measured with dial calipers and the stroke with a two or three inch travel dial indicator.        B. The following formula will be used for calculating displacement; BORE X BORE X STROKE X .7854 X 16.39 = CC of engine. (this assumes that the bore and stroke were measured in inches. The 16.39 is a conversion factor From cubic inches to cubic centimeters.)        C. Always round up to the nearest whole cc when calculating minimum weight.        D. Competitors must declare their weight and display it next to their front number in such a manner that the scale person can easily see it.

Any 4 cycle motor not corresponding to a listed IKF class must use a billet flywheel for safety 4. General Event Related Policies.        A. The driver is the official entry. He / She can switch karts between heats or before the feature, but not during a race. The kart must comply with the minimum weight for that particular kart and display the number with which the driver registered.        B. All Rolling Thunder Speedway rules and regulations will be adhered to by drivers in the Open Class. The show will be run according to their normal procedures unless Rolling Thunder Speedway decides to modify those procedures to improve the event.        C. Rolling Thunder Speedway has the right to refuse any equipment for competition on their track that they feel is unsafe for competition.        D. Only one spin out per heat race or feature race that causes a yellow flag. Those drivers will be black flagged upon their second spin out that causes a yellow flag.        E. The IKF speedway rules for body work have been adopted by the Rolling Thunder Speedway as a general guideline for safety purposes.        F. This program is intended for vehicles classified as go-karts. The go-karts are to be constructed in a safe manner. Maximum overall dimensions will be determined by the least restrictive parameters for any division as generally set forth by IKF, WKA and KART.

Spirit and Intent

Note to Competitors The Rolling Thunder Speedway Open Class is intended to be a Professional series and all drivers and crew members are expected to act accordingly. If you canbt or wonbt drive and act in a professional manner, then race in another division. We donbt necessarily want the most drivers, but we do want the best. Please give your competitors room to race. Respect the other drivers, they have a lot invested too. Rough driving, foul language, and un-sports-man-like conduct are not tolerated. Officials are requested to be especially firm with the Unlimited All-Stars. Remember, a lot of kids look up to YOU. Spirit and Intent The Rolling Thunder Speedway Open Class was created to develop and promote open class kart racing. Innovation is allowed and encouraged. These rules were created to provide parameters for the purpose of safety and cost containment. Generally speaking, if a rule does not specifically state that something is not permitted, then it can be assumed that it is permitted. Any rule adjustments that become necessary to maintain a level playing field due to the introduction of new technology will go into effect the following year.