Mini-Sprint Rules
SPECIFICATIONS:
Engine Definition :
Two engines classifications are legal, any multi cylinder OEM 600 cc
plus .080” (2mm) overbore or Kawasaki 636cc must remain as manufactured with stock OEM configuration (no modifications / no aftermarket parts) engineered to fit in a mini sprint chassis.
1. OEM 600 cc engines are allowed any modifications, but must maintain
their stock stroke.
2. All engines may be converted to alcohol fuel, no fuel additives
other than top end lube allowed.
3. Engines may be fuel injected or carbureted
4. Forced induction (turbos or superchargers) or nitrous systems
prohibited.
No fuel additive except top end lube is allowed. Forced induction such as turbo or superchargers, and any type of nitrous system is prohibited.
- General Information:
- Car must have a cockpit operated electric starter, a lever manual clutch in car, and an on board battery capable of starting a 600cc multi-cylinder engine
- Must remain chain driven off original countershaft (belt drive may run as equal)
- Engines must have been designed for street use on motorcycles ridden in U.S.A.
- Engine displacement will be randomly checked
NOTE: To find the cubic inches of displacement of an engine, measure the bore and multiply it by itself. Then multiply the product by .7854 and multiply that product by the stroke of the engine and multiply that by the number of cylinders. These measurements will give the allowable engine cubic inches weight and classification of the car. Bore x Bore x Stroke x .7854 x 16.35 = Cubic Centimeters.
- Transmissions: Any type transmission is legal. Shifting mechanism must be mounted in the driver's compartment or on the opposite side of the chain guard if mounted outside.
- Roll Cage: Roll cages shall be at least 1 1/18 " (.065 wall), or 1 1/14" (.065 wall). 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 cages shall have sufficient fore and aft bracing and strength to support the weight of the car and driver in case of an upset. Cage shall have gussets at the intersecting bars to the uprights. Bends must have at least 3" radius. No square or pointed corners allowed. Roll cage must be a minimum of 3" above the driver's helmet. A cross bar behind the seat to support the shoulder harness is required.
- Bumpers: Car must have bumpers that extend 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 or the tires. No sharp corners or designs as to hook or damage.
- Nerf Bars: All cars must be equipped with nerf bars. Nerf bars must extend to inside edge of tires, but not beyond the outside of the tires.
- Seat Belts: Seat belts must be securely attached to the car and used at all times. Metal to metal latches only, 5-point seat belts, 3"shoulder harness, and sub strap are required. Belt dates must not be over 3 years old.
- Arm Restraints: Arm restraints are mandatory and must be adequately adjusted to keep the drivers hands below the top of the roll cage.
- Uniform: A name brand flame-retardant is required. Nomex underwear recommended with all uniforms (especially single layer).
- Gloves: Flame-retardant are required.
- Neck Braces: Neck braces and/or cage nets are required.
- Helmet: Helmets must be full head coverage, competition type, and one of the three latest SNELL approvals.
- Electronics: No radio communications allowed. On and off switches must be on dash, top of the cowl or on the steering wheel. They must be functional so that killing the main power will kill the electric pump.
- Battery: Wet cell batteries must be covered and vented outside the cockpit.
- Fuel: Gasoline, ethanol, or methanol may be used.
- Weight. Minimum weight for car and driver is 750 pounds for car and driver with engine displacement up to 619cc. 620cc to 636cc must weigh 825 lbs. with driver. Material used to add weight to the car must be firmly attached as part of the car’s structure. It must be mounted in the area between the counter shaft/clutch cover and the front of the seat. All heat winners will be weighed. Top 5 finishers of the feature will be weighed after the feature.
- Suspension: Any shock absorbers are legal. Rear wheel drive. No dual rear tires. Any size and tire combination may be used, however, tires may not exceed 22 ½ inches in height. Wheels must be held on with 4 or more standard lug nuts or knock-off hubs.
- Tread: Maximum allowed is 50 inches; minimum is 32 inches, measured center to center of tires.
- Wheelbase: Maximum allowed: 70 inches; minimum: 50 inches; measured from center of front axle to center of rear axle.
- Brakes: Brakes will be of sufficient strength so as to slide the wheels while the car is in motion at any given time.
- Bodies: All cars must have complete bodies. Metal firewall between driver and engine made of 24-gauge steel or .0625" aluminum required. Body of cars must be made of aluminum, metal, fiberglass, or high impact plastic (lexan). Cars should be painted an attractive color or colors. No rear view mirrors allowed. The only part of the car that can be dismantled, for the driver to enter or exit, is a quick release steering wheel hub. Mudguards are allowed but must be made of aluminum or fiberglass and can be no less than 16" from the top of cage. All mechanically operated devices must be mounted below the driver's shoulders for safety. Cars must have complete under pan extending from the front of the seat to a place forward of the drivers feet.
- Wings: Top wings are mandatory. Right sideboard can be a maximum of 54"x 24". The left sideboard can be a maximum of 54"x 24". Sides must cover center section. All wings must have 1/16" radius edges or edging. Total size cannot exceed 12 Sq. Ft. (L=36"x W=48"). Nose wings cannot exceed 24" X 18", with 9" X 22" sideboards. Offset wings allowed. Wing sideboards cannot extend beyond the outer edge of either rear tire. No dual stage top or nose wings. Adjustable wickerbill allowed.
- Numbers: Numbers must have legible numbers painted in contrasting colors on both sides of car and the nose or nose wing. Minimum height is 8" on nose or nose wing, 10" on each side of the tail cone, and 12" on the wing. Numbers must be separated from advertising so they will be readable. Numbers can consist of digits, letters, and could be up to 3 in the combination. In the event there are duplicate numbers entered, a florescent colored letter will be added to the latest entered cars number.
- Chain Guard: Chain guards are mandatory. Material will be made of .090 " thick aluminum or equivalent and will run on top of chain from the front of the front sprocket to the center of the rear axle. Driver must not be able to touch the chain or sprockets while sitting in the cockpit.
- Traction Control Devices. These devices are not allowed.
Y. Tires. Anyone claiming 620cc to 636cc engine must run an NMMA spec (durometer 50) on the right rear.
No grooving and no sipeing of the tire.
Anyone claiming 619cc or less can run any tire combination (no tire rule).
Subject to Change Without Notice
