2009
250 Mirco Sprint Rules
Specific Rules:
1. AGE: Drivers age 10 and up may compete in the "Single" Class.
2. Roll Cage: Roll cages shall be at least 1 inch .062 wall thickness. .065 wall thickness allowed on tubing 1 1/8 inch diameter or larger. Roll cage shall be made of chromoly steel or equivalent material. The front section of the cage shall be no further back than the steering wheel. Roll cage shall have sufficient fore and aft bracing and strength to support the weight of the car & driver in case of an upset. Cage shall have gussets at the intersecting bars to the uprights. Bends must have at least 3 inch radius. No square or pointed corners allowed. Roll cage must be a minimum of 3” above the drivers helmet. It is mandatory to install a cross brace behind the seat to support the shoulder harness.
3. Bumpers And Nerfs:Car must have bumpers extending beyond the front and rear tires. Nothing may extend beyond a tangent line from the outside edge of the tires to the bumpers. Nothing may extend beyond the outside edge of the tires or wheels, whichever is the widest. No sharp corners or design as to hook or damage. All cars must be equipped with nerfing bars. Nerfing bars must extend to inside edge of tires, but not beyond the outside of tire.
4. Safety:Seat belts must be securely attached to the car and used at all times. Metal to metal latches only. 5 point seat belts, shoulder harness and sub strap are required. Belt dates must not be over three years old. (Example: Oct 06 may be used in 2007, 2008 and 2009.) Arm restraints are mandatory and must be adequately adjusted to keep the drivers hands below the top of the roll cage. Helmets must be full head coverage, competition type and one of the three latest SNELL approvals. All drivers will wear a name brand flame-retardant uniform. Neck braces, cage nets and/or head and neck restraints are mandatory. SFI gloves are mandatory for safety.
5. Electrics and Electronics:On and off switches must be on dash, top of the cowl. On/off switch must be connected and functional. No radio communication is allowed with the car or the driver.
6. Battery: All wet cell batteries mounted in the cockpit must be covered and vented outside the cockpit area.
7. Fuel:"Single" Class cars may run gasoline, ethanol or methanol. No performance enhancing additives are allowed!
8. Weight:"Single" Class cars, minimum car and driver weight 600 lbs.
9. Brakes: Brakes will be of sufficient strength so as to slide the wheels while the car is in motion at any given time.
10. Shocks: Any shock absorber is legal.
11. Suspension: Tread; Maximum 63 inches outside to outside of rear tires. Minimum 32 inches, center to center of tires. Wheelbase; Maximum 70 inches. Minimum 50 inches, center of front axle to center of rear axle. Steering: Front wheels must be connected by a solid or tubular tie rod. Rear wheel drive only. All suspension bolts except wheel nuts must be secured by some type of locking device.
12. Wheels and Tires: Any wheel size and tire combination may be used. Wheels must be held on with 4 or more standard lug nuts or knock-off hubs.
13. Bodies: All cars must have complete bodies. Tail sections must be in place for time trials and all races. There must be a metal firewall between driver and engine, made of 24 gauge steel or .0625" aluminum. No rear view mirrors. Rule 1975.3(p). The only part of the car allowed to be dismantled for driver to enter or exit is a quick release steering wheel hub. The minimum opening on the right side of the car will be 13” from the bottom of the roll cage to the top of the mud guard or sissy bar and 16” minimum width (a 1” tolerance in either direction is allowed). All mechanically operated devices must be mounted below the driver’s shoulders for safety. All fuel tanks must be equipped with a one-way check valve designed to prevent the spillage of fuel from the fuel tank vent in the event of a rollover. Body Panels may not extend more than 1" beyond the rear cage downtubes.
14. Transmissions:Any type transmission is legal. Any car equipped with a shifting mechanism must have this device mounted in the driver’s compartment. Shift levers may be mounted outside the driver’s compartment on opposite side of car from the chain drive.
15. Wings: Cars may run any size top wing. Sideboard, left side, maximum 26” tall x 54” long. Sideboard, right side, maximum 24” tall x 54” long. No part of the wing may extend beyond the width of the tires as driven (including but not limited to the center section, sideboards, or bracing). Top wings are mandatory to enter a night's event. Cars may finish without a wing if no replacement is available. If a nose wing is used, the center section may not exceed 18” x 24” with sideboards no larger than 9” tall x 21” long.
16. Ballast: Any material used for ballast must be firmly attached as a part of the car's structure. No loose ballast allowed.
17. Numbers:All cars must have legible numbers on both sides of car and the nose. Minimum height of numbers is 8" on the nose or nose wing, 10" on each side of the tail and 12" on the wing.
18. Engines:Any single cylinder 2-stroke motorcycle engine no larger than 270cc. No Billet Cranks or No Vortec CDI box. Here is the max engine bore and stroke you can run. 72 stroke x bore 69 - 74 stroke x 68 bore - 76 stroke x 67 bore - 77.5 stroke x stock bore and 78 stroke are illegal, becasue the stock bore make it over 270cc. If you are running something bigger then listed your motor is illegal
19. Rules Infractions: If any competitor is found to have illegal parts or non functional components at any time, they will lose all points and/or money for that night.
RULES, COMPONENTS, OR PROCEDURES SPECIFICALLY NOT MENIONED AS BEING ALLOWED ARE ILLEGAL UNLESS APPROVED AHEAD OF TIME BY THE HIGH PLAINS MICRO SPRINTS ASSOCIATION TECHINAL DIRECTOR.