| NTK Class Structure* | |||||||||||
| Class | Age | Engine | Rule Book | Weight | Tires | Front Tire | Rear Tire | Pipe | Slide | Silencer | Other |
| Kid Karts | |||||||||||
| Kid Kart Comer | 5-7 | C-50/C-51 | IKF | 160 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| Kid Kart Honda | 5-7 | GXH50 | Honda | 160 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| Kid Kart Bambino | 5-7 | IAME Bambino | USPKS | 160 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| Kid Kart 206 | 5-7 | LO206 Jr | Briggs | 175 | Evinco Blue | 4.60-5 | 4.60-5 | #5507 | .285” - Black - #555728 | #4104 | Carb Lock |
| Cadets | |||||||||||
| 206 Jr. 1 | 8-12 | LO206 - Blue Slide | Briggs | 240 | Evinco Blue | 4.60-5 | 4.60-5 | #5507 | Blue - #555734 | #4104 | Carb Lock |
| Rookie Sportsman | 8-11 | KT100 | IKF | 235 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| TaG Cadet 1 | 7-10 | Micro ROK | ROK Cup USA | 225 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| Micro Swift | SKUSA | 225 | |||||||||
| TaG Cadet 2 | 9-13 | Mini ROK | ROK Cup USA | 245 | Evinco Blue | 4.60-5 | 4.60-5 | ||||
| Mini Swift | SKUSA | 245 | |||||||||
| Juniors | |||||||||||
| 206 JR. 2 | 12-15 | LO206 | Briggs | 310 | Evinco Blue | 4.60-5 | 6.00-5 | #5507 | Yellow - #555741 | #4104 | Carb Lock |
| Jr. Super Sportsman | 12-15 | KT100 | IKF | 300 | Evinco Blue | 4.60-5 | 6.00-5 | ||||
| 100 CC Jr. | 12-15 | ROK VLR | ROK Cup USA | 320 | Evinco Blue | 4.60-5 | 7.10-5 | ||||
| IAME KA100 | SKUSA | 320 | |||||||||
| TaG Jr. | 12-15 | IAME X30 | SKUSA | 320 | Evinco Blue | 4.60-5 | 7.10-5 | ||||
| ROK GP | ROK Cup USA | 320 | |||||||||
| Rotax Jr. Max | TaG USA | 320 | |||||||||
| Seniors | |||||||||||
| 206 Sr. | 16+ | LO206 | Briggs | 360 | Evinco Blue | 4.60-5 | 6.00-5 | #5507 | Black - #555590 | #4104 | |
| 206 Heavy | 16+ | LO206 | Briggs | 390 | Evinco Blue | 4.60-5 | 6.00-5 | #5507 | Black - #555591 | #4104 | |
| Sr. Super Sportsman | 16+ | KT100 | IKF | 340 | Evinco Blue | 4.60-5 | 7.10-5 | ||||
| 100 CC Sr. | 16+ | ROK VLR | ROK Cup USA | 360 | Evinco Blue | 4.60-5 | 7.10-5 | ||||
| IAME KA100 | SKUSA | 360 | |||||||||
| TaG Sr. | 16+ | IAME X30 | SKUSA | 365 | Evinco Red | 4.60-5 | 7.10-5 | ||||
| ROK GP | ROK Cup USA | 380 | |||||||||
| Rotax Max/EVO | TaG USA | 380 | |||||||||
| 100 CC Master | 30+ | ROK VLR | ROK Cup USA | 380 | Evinco Blue | 4.60-5 | 7.10-5 | ||||
| IAME KA100 | SKUSA | 390 | |||||||||
| TaG Masters | 30+ | IAME X30 | SKUSA | 395 | Evinco Red | 4.60-5 | 7.10-5 | ||||
| ROK GP | TaG USA | 405 | |||||||||
| Rotax Max/EVO | TaG USA | 410 | |||||||||
| Shifter | 16+ | Honda CR125 | SKUSA | 385 | Evinco Red | 4.60-5 | 7.10-5 | ||||
| ROK Shifter | ROK Cup USA | 405 | |||||||||
| IAME 175 | SKUSA | 415 | |||||||||
| ICC/KZ | 410 | ||||||||||
| * Engines not listed in class structure will run with an appropriate class but will not score points | |||||||||||
| * For full class details see current NTK Rulebook | |||||||||||
| * Weights may be adjusted for Local Option Rules | |||||||||||