Below is the WKA 2026 dirt class structure as published by World Karting Association. Use it to figure out where your driver fits before you buy a chassis or set up for a weigh out. Then verify it against the rulebook, because the rulebook is the authority, not this page.
The classes
| Class | Age | Minimum weight | Plate |
|---|---|---|---|
| Future Stars | 8 and under | 235 lb | Red Plate |
| Red Plate Champ | See rulebook | 275 lb | Red Plate |
| Junior 1 | 10 and under | 275 lb | Green Plate |
| Junior 1 Champ | See rulebook | 285 lb | Green Plate |
| Junior 2 | 12 and under | 290 lb | Purple Plate |
| Junior 2 Champ | See rulebook | 315 lb | Purple Plate |
| Junior 3 | 15 and under | 320 lb | Blue Plate |
| Junior Champ | See rulebook | 355 lb | See rulebook |
| Junior Stock | 12 to 15 | 325 lb | See rulebook |
| Ducar | 14 and up | 375 / 400 / 425 lb | See rulebook |
| No Pro | See rulebook | 375 lb | See rulebook |
| Clone Medium | See rulebook | 350 lb | See rulebook |
| Senior Limited | See rulebook | 390 lb | See rulebook |
| Champ Senior | See rulebook | 425 lb | See rulebook |
| Senior Clone | See rulebook | 375 / 390 / 400 lb | See rulebook |
| Super Heavy | See rulebook | 425 lb | See rulebook |
| Unlimited All-Stars | See rulebook | See rulebook | See rulebook |
Where a cell says "see rulebook," the figure is not something we are going to guess at in print. Pull the PDF or call your track.
Age is the boundary, and it is enforced
The junior classes are drawn by age, not by size, ability or how long a kid has been racing. A 13 year old does not run Junior 2 because he is small. Tech can and will ask for proof of age, and the class you sign up for on the entry form is the class you are legally in.
Cutoff dates matter. Whether a driver's age is taken as of January 1 or as of the race date changes which classes he is eligible for that season. That detail lives in the WKA age eligibility document, and it is worth reading once at the start of the year rather than arguing about it in the tech line.
Weight is kart plus driver, at weigh out
Every number in the table above is a minimum, and it is the kart and the driver together, weighed after the race, in the gear he ran in. Not the kart on the scale in your shop on Tuesday.
Practical consequences:
- You lose weight over a feature. Sweat, fuel burn and thrown mud all come off between the green and the scale. Build in margin.
- Lead has to be mounted the way the rules say it is mounted. Bolted, and in some cases safety wired or double nutted. A bar that comes off on the track is a disqualification at best.
- Cross weight and left side percentage are your setup levers, but they do not change total weight. Get legal first, then chase the setup.
- Check your scales against the track's scales early in the season. Two sets of scales rarely agree, and the track's number is the one that counts.
If you want a second set of eyes on it, we offer a Weigh Out Kart service. We will put the kart and driver on the scales, tell you where you actually sit, and show you what the corner weights look like before you find out in tech.
Plate color signals the restrictor
WKA dirt uses plate color as shorthand for the restrictor a class runs. Red, Green, Purple and Blue each correspond to a specific restrictor plate. When someone at the track says a kid is "on a green plate," that is the class and the restrictor in one word.
Note the terminology, because it trips up people coming from asphalt or from other sanctioning bodies. WKA dirt does not use "Kid Kart." The 8 and under class is Future Stars, and it runs the Red Plate.
The plate is a tech item. Sizes, stampings and how the plate is to be installed are specified in the rulebook, and tech will check it. Do not run a plate you got from someone in the pits without confirming it is the right one for your class.
The rulebook and your track are the authority
Two things to keep in mind about anything you read here:
First, WKA updates its rules. Weights, ages and class names change between seasons and can be amended in-season through bulletins. What is on this page reflects the 2026 documents linked below at the time we wrote it. Always pull the current PDF yourself.
Second, local tracks run their own variations. A weekly track may run a class at a different weight than the national number, may combine two classes to fill a field, may add a house class that WKA does not have, or may not run a listed class at all. None of that is unusual. Call the track or read their posted rules before you tow.
Official sources:
Getting the chassis size right
Class also drives what chassis you need. Our frames are built in JR1, JR2 and Adult sizing, and the sizing is about fitting the driver, not just the class number. A driver who has outgrown his seat is slow and uncomfortable no matter how good the setup is.
Current models are the Fanatic, Fanatic ST, Fanatic Champ and Fanatic Jr Sportsman Champ, available as Frame Only, Standard, F1 and F1 Jr packages. You can see what we have at complete chassis.
Not sure which size and package fits your driver and the class he is running? Call us at 864-269-8947. We would rather talk it through than have you buy the wrong frame.