From WKA http://www.worldkarting.com/series/roadrace/roadraceclasses.html
at least this shows the motos.
ROAD RACING CLASSES – SPRINT
BRIGGS SPRINT 335/360
DRIVER REQ: Age 15 or older. Class 2 Road Racing License.
ENGINE: Briggs & Stratton 5HP. See Section 701, except rod & piston, see section 702. Silencer Mandatory
MIN. WEIGHT: 335/360
BRIGGS JR SPRINT LITE & HEAVY
DRIVER REQUIREMENTS: Age 12 thru 15 only, Class 2 Road Racing License.
ENGINE: Briggs & Stratton 5hp, see section 701, with .575 restrictor plate, except rod & piston, see section 702 with .575 restrictor plate. Silencer Mandatory.
MIN. WEIGHT: 295 lb. (LITE)
MIN. WEIGHT: 315 lb. (HEAVY)
OTHER: All engine rules same as Briggs Sprint with addition of .575 restrictor.
JR SPRINT LITE & HEAVY
DRIVER REQ: Age 12 through 15 only, Class 2 Road Racing License.
ENGINES: Yamaha (Only heads with OEM casting ?Yamaha? and cylinders with Y3 or Y4 and 787 are legal), ARC Comer, and PRD RK100.
EXHAUST: RLV YBX #7500. If hole exists in pipe for EGT sensor, EGT sensor probe must be in place.
FUEL: Gas and oil only.
MIN. WEIGHT: 295 lb. (LITE)
MIN. WEIGHT: 315 Lb. (HEAVY)
PISTON PORT CAN SPRINT 340/360/380
DRIVER REQ: Age 15 or older. Class 2 Road Racing License.
ENGINES: Yamaha (only heads with OEM casting ?Yamaha? and cylinders with Y3 or Y4 and 787 are legal), ARC Comer & PRD RK 100.
EXHAUST: RLV SSX 7502, 7540, 7541, 7542, 7543, 7544, and SSXV 7548. When a SSX Muffler # 7540 is used, it must be run with 4 holes up and part # 7502 must be run with 4 holes down. When an SSX Muffler # 7541 is used, it must be run with 4 holes pointed in the upper left direction. When an SSX #7543 is used, it must be run with 4 holes pointed in the upper right direction. If a hole exists in pipe for EGT sensor, the EGT sensor probe must be in place.
FUEL: Gas and oil only.
MIN. WEIGHT: 340 lbs.
MIN. WEIGHT: 360 lbs.
MIN. WEIGHT: 380 Lbs.
OTHER: 380 class will have a 200 lbs. maximum kart weight.
NOTE: MAX. Kart weight of 200 lbs at post race for the 380 class and if race is red flagged before its proposed time, an allowance of up to 204# per kart weight is acceptable.
WKA SPRINT LITE & HEAVY
DRIVER REQ: Age 16 and older. Class 2 Road Racing License.
ENGINES: Yamaha KT100S (only Yamaha heads with OEM casting ?Yamaha? are legal), ARC Comer, & PRD RK100 and Piston Port.
EXHAUST: Any Fixed WKA approved pipe (No Adjustable pipes allowed)
FUEL: Gas and oil only.
MIN WEIGHT: Yamaha, ARC & PRD 315 lb. (LITE)
MIN WEIGHT: Piston Port 340 lb. (LITE)
MIN WEIGHT: Yamaha, ARC & PRD 340 lb. (HEAVY)
MIN WEIGHT: Piston Port 365 lb. (HEAVY)
NOTE: MAX. Kart weight of 200 lbs at post race for Heavy class and if race is red flagged before its proposed time, an allowance of up to 204# per kart weight is acceptable.
YAMAHA SPRINT LITE & HEAVY
DRIVER REQ: Age 16 and older. Class 2 Road Racing License.
ENGINE: Yamaha. Only heads with OEM casting ?Yamaha? are legal.
EXHAUST: Any fixed WKA approved pipe (No Adjustable pipes allowed)
FUEL: Gas and oil only.
MIN WEIGHT: 335 lb. (LITE)
MIN WEIGHT: 360 lb. (HEAVY)
NOTE: MAX. Kart weight of 200 lbs at post race for Heavy class and if race is red flagged before its proposed time, an allowance of up to 204# per kart weight is acceptable.
WKA/ICC 125 SPRINT 1 and 2
DRIVER REQ: Age 18 or older. Class 2 Road Racing license & Class 1 Sprint license OR Class 1 Road Racing license. Any 17 year old competitor may enter provided he/she meets all of the following requirements: currently possesses a Class 2 Road Racing license & Sprint Class 1 license (OR Class 1 Road Racing license) and must have competed at any WKA sanctioned national or regional event in the CIK or WKA 125 Sprint classes in the 2003 season.
ENGINES: (1) Mass produced, single-cylinder, motorcycle engines of up to 125cc displacement, currently available production, approved by WKA: Honda CR Reed, Kawasaki KX Reed, Suzuki RM Reed, Yamaha YZ Reed, Gilera 125cc and TM Motocross will be allowed. (See section 613 for specifications). All engine specs must be unaltered OEM parts unless otherwise specified in this manual. All competitors must be prepared to produce verification documentation of proper dimensions and component data for the engine utilized for competition prior to the time of post tech inspection.
(2) ICC engines with homologated pipe and 30 mm carburetor.
EXHAUST: Motorcycle engines – Any fixed WKA approved pipe (No adjustable pipes allowed) with silencer. ICC engines ? stock homologated ICC pipe and silencer.
INTAKE SILENCER: ICC requires stock, homologated airbox. Motorcycle requires airbox (see 551.1.3) and/or air filter. Where specific track or ordinances requires the use of an airbox, this will be noted on entry form. Competitor is responsible to maintain compliance with any rules or ordinances regarding noise regulation.
FUEL: Gas and oil only.
MIN WEIGHT: Motorcycle engines with WKA bodywork – 385 lbs.
MIN WEIGHT: Motorcycle engines with CIK bodywork ? 365 lbs.
MIN WEIGHT: ICC engines with CIK bodywork ? 385 lbs.
TIRES: Open Compound, 5″ or 6″ Diameter Rims, Rear Tires 7.00″ Min. Width
OTHER: (1) Motorcycle powered karts at 365 lbs. and ICC karts must run CIK style bodywork only, either conforming to all dimensions listed in section 200 or CIK approved bodywork that is readily available at least 90 days prior to the beginning of the racing season. Carbon fiber, Kevlar and metal are not legal construction materials for nose, side pods and steering fairing. Karts with motorcycle engines at 385 lbs may run full WKA sprint bodywork. WKA sprint bodywork, bumper and nerf bar rules apply to these karts, except that the minimum bodywork width, as defined in 358.6.6, shall be 42?. Either CIK style side pods or Sprint Enduro side panels are allowed with WKA bodywork at 385 lbs. (2) Radiator must be mounted on the right or left side of the driver between the tires. (3) All karts must utilize lower bumper cross-bar (see 209.3.5). (4) Standing start procedure utilized.
CIK 125 SPRINT 1 and 2
DRIVER REQ: Age 18 or older. Class 2 Road Racing license & Class 1 Sprint license OR Class 1 Road Racing license. Any 17 year old competitor may enter provided he/she meets all the following requirements: currently possesses a Class 2 Road Racing license & Sprint Class 1 license (OR Class 1 Road Racing license) and must have competed at any WKA sanctioned national or regional event in the CIK or WKA 125 Sprint classes in the 2003 season.
ENGINES: Mass produced, single-cylinder, motorcycle engines of up to 125cc displacement, currently available production approved by WKA: Honda CR Reed, Kawasaki KX Reed, Suzuki RM Reed, Yamaha YZ Reed, Gilera 125cc and TM Motocross will be allowed. (See section 613 for specifications). All engine specs must be unaltered OEM parts unless otherwise specified in this manual. All competitors must be prepared to produce verification documentation of proper dimensions and component data for the engine utilized prior to the time of post tech inspection.
EXHAUST: Any Fixed WKA approved pipe (No Adjustable pipes allowed)
INTAKE SILENCER: Airbox (see 551.1.3) and/or Air Filter Required. Where specific track or ordinances requires the use of an Airbox, this will be noted on entry form. Competitor is responsible to maintain compliance with any rules, or ordinances regarding noise regulation.
FUEL: Gas and oil only.
MIN WEIGHT: 385 lbs
TIRES: Open Compound, 5″ or 6″ Diameter Rims, Rear Tires 7.00″ Min. Width
OTHER: (1) CIK style bodywork only, either conforming to all dimensions listed in section 200 or CIK approved bodywork that is readily available at least 90 days prior to the beginning of the racing season. Carbon fiber, Kevlar and metal are not legal construction materials for nose, side pods and steering fairing. (2) Radiator must be mounted on the right or left side of the driver between the tires. (3) All karts must utilize lower bumper cross-bar (see 209.3.5). (4) Standing start procedure utilized. (5) Rear track width must be a minimum of 50? and a maximum of 55 1/8?.
Spec 125 Sprint
DRIVER REQ: Age 16 or older. Class 2 Road Racing license & Class 1 Sprint license OR Class 1 Road Racing license
ENGINES : Rotax Max, Parilla Leopard, Comer (Check future Tech Updates for technical regulations on Parilla Leopard, Comer, and any additional engines that may be added.)
AIRBOX: Stock Airbox Required
FUEL: Gas and Oil only
MIN WEIGHT: 375 lbs
TIRES : Open tires, rear tires 7? minimum width
OTHER : (1) CIK style bodywork only, either conforming to all dimensions listed in section 200 or CIK approved bodywork that is readily available at least 90 days prior to the beginning of the racing season. Carbon fiber, Kevlar and metal are not legal construction materials for nose, side pods and steering fairing. (2) Radiator must be mounted in the stock location. (2) Belt or chain drives are legal. (3) Dual brake system is required. (3) Kart must meet all 125 Sprint chassis requirements. (4) Standing start procedure utilized. (5) Performance differences between the various manufacturers will be adjusted by kart weight, or restrictions to the engine or exhaust system. WKA will make every effort to make it a level playing field among engine manufacturers.
BRIGGS SPRINT OVER 35
DRIVER REQ: Age 35 or older. Class 2 Road Racing License.
ENGINE: Briggs & Stratton 5HP. See Section 701, except rod & piston, see section 702. Silencer Mandatory
MIN. WEIGHT: 385 lbs.
OTHER: No maximum kart weight