General Track Rules
Go Karts
Greenwood Valley Action Tracks uses the World Karting Association’s motor specs, which can be found at this link – Rule Set.
The age and weight for each class is as follows:
Adult Cage: 16 and over – 410 lbs
Junior Cage: 12-16 – 365 lbs
Rookie Purple: 5-11 – 265 lbs
Rookie Blue: 7-11 – 285 lbs
Kid Karts: 5-7 – 125 lbs
Any interpretation or deviation of these rules is left to the discretion of the officials.
125s Micros RS motors allowed
270 Micro Sprints: These cares are powered by 250cc motorcycle engines bored out to 270 and they are modeled after sprint cars including the need to be pushed started.
600 follow the U6SA Rules:
Transponder Location: Transponders are to be placed 21 inches back from the center of the front axle on the right side.
1. Sprint car appearance required. No rear engine cars or aluminum frames.
2. Body may be constructed of aluminum, metal, fiberglass or high impact plastic.
3. Minimum car weight, with driver, must be 800 lbs. at all times. Any add-on weight must be securely fastened, painted white with car number painted on, and not adjustable
4. Top wing refer to U6SA rule package.
5. Wheelbase must be between 58” to 65” maximum. Must have accessible fuel shut off valve and kill switch clearly marked. No belt drives or centrifugal clutches. Cars must have approved firewall between driver and engine compartment as well as between driver and fuel cell. Fuel cell is recommended. All cars must have side nerf bars, and metal belly pan is required (minimum.040”). It must run from in front of seat forward past driver’s feet. Cars must have front and rear bumper. Rear bumper must be suitable for push starts. No belt driven cars. Driver compartment adjustable suspensions allowed. Wing adjustments are O.K
6. All exhaust pipes must have muffler.
7. Battery must be securely fastened and covered to prevent spillage. All cars must be self-starting at start of all events. If car doesn’t self-start, you will go to the rear of the event.
8. Alcohol or gas. Absolutely no additives allowed; including performance enhancing products. Top end lube is allowed.
9. Seat belts must be 3” wide, 5 point approved racing harness. Helmet (min. SA2010) and approved full face shield required. Approved fire suit mandatory; (NOMEX underwear, headsock, two layer suit is highly recommended). Arm restraints, neck collars or head restraints, and racing gloves must be worn at all times. Chain guard mandatory. Aluminum racing seat is mandatory. Must have headrest and be padded.
10. Overall car width may not exceed 65”, from outside of right tire to outside of left tire. 10” maximum wheel diameter. Must be approved racing wheels. All brakes must be in good working condition.
Engine Rules
1. Engine Rule: Refer to U6SA rule chart.
· Stock parts – original manufacturer parts for the particular year and make engine. No mixing of parts from different year and make engines, even if made by the same manufacturer.
2. Overall Engine
· Must be a Production Motorcycle Engine, 4 cylinder, 4 stroke
· No Titanium anywhere in or on the engine, unless it comes stock form manufacturer of engine on production bike
· Must have engine, clutch, and transmission all in one unit
· Must be Chain Drive
3. Bore and stroke
· 600cc Maximum For engine model that was new in 2006 and up. Other engine are 637cc maximum. Engine model is defined as a manufacturer redesign of overall engine. See list at end of rules.
· Standard Stroke only (no strokers)
4. Head and cams
· NO PORTING, Blending the Bowls, or Blending the Valve Seats (exhaust or intake) Valve jobs are acceptable.
· Cams do not need to be stock, but the lift must be no greater than stock. (duration is open)
· Cam timing may be adjustable
· May use any valves, but they may be no larger than stock valves.
· Head may be resurfaced
· Any head gasket may be used
5. Pistons
· Any Piston may be used, must be within cc limit specified under bore and stroke
6. Bottom End
· No machining to remove weight from the crank (no after-market cranks)
· Stock or after market connecting rods are permitted
· Aftermarket rod bolts may be used
– No polishing of the crank
7. Clutch/Transmission
· The clutch does not need to remain stock, but must remain operable
· Transmission gears must be stock, no close-ratio gears or nonstandard gear-ratios
· All gears must remain in transmission, no removing any gears.
– No polishing of transmission gears
8. Ignition
· Stock Rev Limiter must remain intact. No hot ECU boxes, no modified ECU boxes. Factory race boxes are ok, but must have the rev limit set to the street bike stock rev limit. If a computer is hooked up to check the ECU it must be set to factory stock specifications, no tolerance. See list at end of rules for RPM limits.
· All cars must have a connector for the track to check engine rpm rev limit. These are available from the chassis manufactures and engine builders, and at the track. All cars must leave intact the rpm wire coming from the ECU.
· Stock appearing ignition must be used (no after-market ignition systems, factory race ignitions are ok) may use different year ignitions from same manufacturer as long as stock rev limit of engine (not ignition) is retained.
· No aftermarket coils
· Engines that came with stock fuel injection may use an after-market add ons (example: Power Commander, Dim Sport) to adjust the fuel curve and/or timing (essentially the same as adjusting jetting and using an ignition advancer).
· Ignition advancers may be used
9. Induction system
· No mechanically forced induction (turbo charging, supercharging)
· Any carburetors may be used on any engine, regardless of year.
· If the engine did not come from the factory with fuel injection, fuel injection may not be used
· If the engine came with a factory fuel injection, the fuel injection may be used and may be converted for use with alcohol. The stock fuel injection throttle bodies must remain, but may be modified for use with alcohol
10. Exhaust
· Any exhaust may be used, as long as there is a muffler included with the system that will keep noise levels within individual track limits.
11. Charging system
· The original factory charging system may not be removed, and must remain in complete working order
12. Self Starting
· The engine must self-start at the beginning of the event. If it does not self-start, the car
may be pushed off and must start at the rear of the event as the penalty
13. Fuel
· Alcohol or gasoline may be used (if gasoline is used, a fuel tank bladder must be installed for safety purposes)
· Fuel Bladders will be mandatory in all cars starting in the 2009 racing season
14. Minimum weight
· Minimum weight at all times is 800 pounds, car and driver. If weight is added it must be
firmly bolted in place.
15. Right Rear must have pin installed at ALL times
These rules are intended to be the official track rules. However, we reserve the right to
amend and adjust any of the wording and interpretations as situations arise, either before or after the racing season begins. Any interpretation or
deviation of these rules is left to the discretion of the officials.
Greenwood Valley Action Tracks 