2013RIVERSIDE VINTAGE CLASS STRUCTURE
1. Junior Drivers Rear or Sidewinder karts: 6.1 (100cc) max displacement: single carburetor, maximum
one inch throttle bore.
Dry clutch: Pipes allowed: Hard tires: American engines.
2. Sportsman Single engine: 8.2 (135cc) max displacement: Oil clutches OK: No disc clutches:
Rear or Sidewinder Pipes OK: American engines only: West Bend 820 must be industrial type, single HL
Carburetor, stock V reed manifold. MC must be 6.1 (100cc) max displacement: No 91
92,93. MC must run small single reed manifold: Single carburetor. HL or small Mac
Flatback OK. Hard tires. This is an entry level class.
3. Historic 1956 to 1962 Historic Karts and Engines. Dry clutch: Single, Twin,Triple engines: 16.5
(270cc) max displacement: No expansion chambers: Mufflers recommended: Hard tires
4. Mac 49 Rear engine karts: 80 cc McCulloch engines: stock condition except aftermarket small intake
manifold allowed: HL carburetor allowed: Dry clutch: Box muffler: Hard tires.
5. Single Rear 6.1 6.1 (100cc) max displacement: American or Foreign engines: Pipes allowed: Oil clutches
allowed, no disc clutches: Hard tires.
6. Single Rear 8.2 8.2 (135cc) max displacement: American or Foreign engines: Pipes allowed: Oil clutches
Allowed, no disc clutches: Hard tires.
7. Dual Rear 16.5 (270cc) max displacement: American or Foreign engines: Pipes allowed: Oil clutches
allowed, no disc clutches: Any Historic C class kart may run in this class: Hard tires.
8. Single Sidewinder 6.1 (100cc) max displacement: American or Foreign engines: engine clutches only: Pipes
6.1 allowed: One inch axle.
9. Single Sidewinder 8.2 (135cc) max displacement: American or Foreign engines: engine clutches only: Pipes
8.2 allowed: One inch axle.
10. Dual Sidewinder 16.5 (270cc) max displacement: American or Foreign engines: engine clutches only: Pipes
allowed: 1 ¼ inch axle allowed if original.
11. ’80-85 Sidewinder 6.1 (100cc) max displacement: American or Foreign engines: Engine clutches only: Pipes
allowed: 1 ¼ inch axle allowed.
12. Senior Sportsman Driver: 60 yrs+: 6.1 (100cc) max engine size: American engines only: Oil clutches OK
Rear No disc clutches: pipes allowed: Hard tires
HARD TIRES: Vintage style, 65 min. durometer @70 deg tire temp. No modern tires, i.e. Bridgestone,
Dunlop,Maxis etc.
CLASSES 8,9,10&11 1979 and earlier sidewinder karts. Modern type tires allowed: 60 min durometer @70
deg. tire temp.
ENGINE
MODIFICATIONS: Allowed with vintage period correct components.
HL CARBURETOR: Tillotson one inch throttle bore-7/8 inch venture maximum.
DIRECT DRIVE: Allowed in all classes.
FUEL: Gas and Oil or Alcohol and Oil only
KART CHASSIS: To remain in their original design from their model year. Brake upgrades allowed.
Reproduction and Specials allowedbut must be vintage type.
ANY REAR ENGINE CLASS KART WITH SIDEWINDER CLASS TIRES WILL BE MOVED UP TO THE CORRESPONDING SIDEWINDER CLASS.
THE SPIRIT AND INTENT OF THE GUIDELINES IS GOING TO BE THE STANDARD BY WHICH THIS EVENT
WILL BE RUN. VKA TIRE GUIDELINES WILL BE USED FOR THIS EVENT
Some classes may be combined but scored separately if needed