2009

MODIFIED CLASS RULES

1.         Engines:  Must have originally been produced for riding lawn mowers.

·        5-20 horsepower single or twin cylinder.

·        Four cycle, gas only.

·        Horizontal or vertical shaft.

·        Engine modifications:  Engine must be stock.  No internal modifications allowed.  May be rebuilt, but will not exceed manufactured stock specifications.  Performance enhancing parts can be used (updated factory parts such as rods, pins, etc).  Ignition must be stock.  Older points systems amy be upgraded to electronic ignition.  External modifications limited to different carburetor, removal of stock exhaust, replacing with header type, disconnecting governor, and replacing or modifying air filter, exhaust must be directed down or to the rear of mower.  Crankcase ventilation system may also be modified.

2.         Starters:  Electric or pull start only.  No push starts.  Battery must be securely fastened.  Battery terminals must be insulated with cover or heavy tape.

3.         Gas tank and fuel systems:  Gas tank must be securely mounted and reasonably protected.  Pump fuel only, additives optional.  In line fuel shut off valve mandatory.  No fueling a running engine.  Nitrous oxide, nitro methane or alcohol MAY NOT BE USED.

4.         Throttles:  Any type throttle may be used:  twist grip, thumb throttle, squeeze grip or foot pedal.  Must operate freely and have operable return spring.  No fixed throttles.

5.         Safety Kill Switch:  Must have a breakaway type, grounded safety switch (TETHER type is mandatory).  For example, types found on boats, wave runners, and quad runners.  If an electric fuel pump is being used, kill switch must disengage electrical power to all circuits.

6.         Transmission/rear axles:  Must be from a lawnmower.  Solid axle recommended.  Differential may be locked.  May be strengthened or remade from heavier steel.  The maximum width of the axles is 38 inches (that’s the measurement from outside tire to outside tire).

7.         Frame/front axle:

·        Frame:  Must use lawnmower frame, may be reinforced.  May be a minimum of 6 inches off ground at lowest part of frame.  It may be no longer than 60 inches long (that’s the distance from front spindle to rear axle).  Front axle may be pinned, bolted or welded in place.  No type of suspension.

·        Front axle:  No go-kart type spindles allowed.  Spindle bushings must be in good condition.  Steering arms and tie-rods must be a minimum of 3/8-inch diameter.  Double locking device highly recommended on front spindles (pinned, bolted, welded or a nut to keep on front tire and wheel.  A standard C-clip that’s on most mowers is not sufficient but may be used with another type of locking device).  Front axle may be fabricated from heavier steel, not to exceed 38 inches wide, outside of tire to outside of tire.  Camber and caster may also be modified.

8.         Tires and wheels:  You may use steel or aluminum wheels, 6-inch front and 8-inch rear.  Wheels with bearings instead of bushings are highly recommended.  FRONT TIRES MUST HAVE TUBES.  No ATV, snow hogs or go-kart tires allowed.  Turf style tires only.  No larger than 20 inch tires.  If using wheels with bushings then bushings must be in good condition.

9.         Belts/pulleys/chains:  Any pulley configuration allowed.  Any pulleys or belts exposed must have guards or covers.  No torque converters or centrifugal clutches allowed.

10.       Brakes:  Brakes must be in working order.  Better braking systems are highly recommended.

11.       Body:  Body must be stock.  All body parts must be mounted securely.  Hood must also lock in place.  The body must have contrasting numbers, one on each side and one on the rear.  A form of mowing deck must be used to appear to be a lawnmower.  Stock mowing decks may be cut down or running boards designed to look like a deck may be used.  Deck must be 2 ½ inches from the ground or higher.  Steering wheels or handlebars allowed.

12.       Bumpers:  Safety bars and front bumper not recommended, but allowed.  It may not exceed half the width of the front tires.  It may not exceed more than 2 inches in front of the front tires.  Rear bumper may not exceed the width of the rear tires.  It may not exceed more than 2 inches behind the tires.   Running board may not exceed the width of the tires and must be securely fastened to the frame of the mower.  Mowing deck may exceed width of tires if in stock form, it may not be widened and can be used for running boards.  Foot pegs are not allowed.