All classes


LAWNMOWER RACING CLASSES AND RULES

Feburary 2013

Class 1 Stock Mower

Class 1 stock mower means a lawn mower, which has not been altered in any way from the manufacturers' original specifications.
Governed engines, 3650 RPM max. (No load)
Any replacement parts used must be exact replacements for original and may
not offer any improvements in power or reliability over the stock part.

Blades or cutters: Every mower shall have the blades or cutters removed or disabled.

Battery: All positively charged terminals must be insulated with a cover or heavy tape, and battery must be well secured.

Cut-off switch: All participating mowers shall be fitted with an operational cut off switch of an approved type.

Brakes: All mowers must be fitted with an effective braking system.

Sharp or dangerous protrusions: Mowers, which have sharp or dangerous protrusions, shall be deemed ineligible for participation. Glass headlights must be taped or removed. No axle or wheel mounting bolts may protrude beyond the face of the tire sidewall.

Safety: Mowers must be safe and complete, all parts and panels in place, with no missing nuts, bolts, cotter keys, etc.
All exposed chains and sprockets must be fitted with metal guards, which will
direct a broken chain downward.
Mowers must be neat and clean, with paint in new or very good condition. No excess dirt, oil, grease, rust or primer. Sponsor graphics must not interfere with mower's racing numbers or class letters.

Race numbers: Every mower shall be issued with a race number, which is assigned by the Secretary of the Association. Race numbers shall be displayed on the side or rear of all mowers, be around 150 mm in height and width and a contrasting colour to the mower.

Subsequent technical inspection requirement: Any mower deemed ineligible for participation due to sharp or dangerous protrusions or that is involved in an incident causing accidental damage during a race must be re-inspected by the Technical Inspector and approved.

MODIFIED CLASSES

Class 1 Modified Mower

Engines originally manufactured for lawnmowers, up to 28ci flat head single cylinder.

Engine may be internally and externally modified.

Class 2 Modified Mower

Engines originally manufactured for lawnmowers, up to 32 ci OHV single or twin cylinder.

Engine may be internally and externally modified.

Class 3 Modified Mower

Engines originally manufactured for lawnmowers, 32 ci and over single or twin cylinder.

Engine may be internally and externally modified.

GENERAL RULES FOR MODIFIED MOWERS

Intent. The intent of these rules is to keep mowers looking like lawnmowers and keep the grass roots style of cost effective racing.

Driveline: Driveline may be modified from the engine pulley to the rear wheels, but must utilize a lawnmower transmission, transaxle or right angle drive.Engine must be within 100mm of the original location.
Rear axle may use open differential, locked, "live" or solid axle. No single wheel drive. Must use at least one drive belt.
Centrifugal and or torque converter clutches not recommended.Rear axle should use shaft locks, centre bolts, or thru-bolts to secure the rear wheels. Maximum diameter 25.4mm.(1")

Brakes: Must use axle mounted brakes, no lawnmower transaxle or transmission mounted brakes.

Steering: All steering linkages must use ball-type or spherical threaded rod ends.
Front axle must be pinned, bolted or welded. No suspension, no shock absorbers. Axles must have a 1-piece beam.
Front axle and steering may be reinforced, substituted or fabricated. In the case of racer-fabricated axles, these will be subject to the judgment of the Technical Inspector as to their apparent safety for racing.

Aluminium may not be used as the material for the one piece axle.

Front Wheels: Shaft locks, centre-drilled axle with locking bolts, castellated nuts with cotter pins, are acceptable for securing front wheels. E-rings and C-rings alone, bent nails, hitch pins, over-centre pins and quick-release pins are not sufficient for wheel retention and are not approved. Bearing wheels are highly recommended

Body:The Original 70% rule has been withdrawn however, We recommend  the use of 100% of body panels, bonnets, gaurds etc. The original Steering support panel/bulkhead should be used in its original configuration. The intent of lawnmower racining is to have mowers look like mowers not go karts or quad bikes. If in doubt ask a club official before you commit to a build.

Chassis:The original 60% rule has been withdrawn, However we recommend the use of 100% of the chassis . This can be discreetly strenthened and modified to allow the fitment of brakes , gearboxs etc. The intent is to prevent space frames being built with mower parts added. Again the intent is to keep the mower looking like a mower. If in doubt ask a club official before you commit to a build.

Grandfather Rule: All mowers that currently race with be able to continue with there current chassis configuration. However they cannot be sold as a legal mower.

Controls: Throttle controls may be relocated. Throttle must return to idle when released. All mowers must have brake controls fitted to either the steering wheel or foot area and be easily activated at all times.

Exhaust: Exhaust design is open, but must terminate away from driver in a rearward and/or downward direction and present no apparent safety hazard.

Starter: Starter must be onboard, either electric or pull-rope.

Overall Width: The maximum width of any mower shall be 1.0 metres (39.4") at the widest point.

Footholds: Footholds must be discrete, and no more than 50 mm ( 2" ) high, made of flat or "L" stock (no rod stock), and made such that the foot can not become entangled in a rollover.

Blades or Cutters: All mowers shall have the blades or cutters removed.

Battery: All positively charged terminals must be insulated with a cover or heavy tape, and the battery must be well secured.

Cut off switch: All participating mowers shall be fitted with an operational cut off switch of an approved type which is connected to the driver by means of a lanyard. Electric fuel pumps must be deactivated with removal of the cutoff lanyard.

Flywheels: Factory flywheels must remain stock. No modifications including lightening, removal of fins or alternator magnets is permitted.

Sharp or dangerous protrusions: Mowers, which have sharp or dangerous protrusions, shall be deemed ineligible for participation. Glass headlights must be taped or removed. No axle or wheel mounting bolts may protrude beyond the face of the tire sidewall.

Safety: Mowers must be safe and complete, all parts and panels in place, with no missing nuts, bolts, cotter keys, etc.
All exposed chains and sprockets must be fitted with metal guards, which will
direct a broken chain downward.

Steering wheels only, no protruding bars.
Mowers must be neat and clean, with paint in new or very good condition. No excess dirt, oil, grease, rust or primer. Sponsor graphics must not interfere with mower's racing numbers or class letters.

 Rear Wheels: Wheels must be the same size on each axle, of any origin, made of metal, minimum 8" , maximum 10" diameter. Rear axle should use shaft locks, centre bolts or thru-bolts to secure rear wheels. No dual or tandem wheels.

Front wheels: Maximum of 6" diameter, use of go kart rims is not encouraged.

Ride height: Lowering is recommended

Seat: The driver's seat must be of reasonable strength and not impede the drivers exit. Automotive or race car/kart type seats are not recommended.

Tyres: Tyres, which are fitted to any competition mower, must comply with the following—
1. Agricultural or flotation type ATV tyres are prohibited
2. Speed rated radial tyres as used on racing ATVs can to be used on front
3. Both tubeless or tube type tyres can be used unless prohibited by organisers
4. The use of knobbly tyres or smooth pattern tyres on the drive wheels will depend on the ruling by event organisers.

Race numbers: Every mower shall be issued with a race number, which is assigned by the Secretary of the Association. Race numbers shall be displayed on the side or rear of all mowers, be around 150 mm in height and width and a contrasting colour to the mower.

Subsequent technical inspection requirement: Any mower deemed ineligible for participation due to sharp or dangerous protrusions or that is involved in an incident causing accidental damage during a race must be re-inspected by the Technical Inspector and approved.