📏 RC Comp Classes
New to competition crawling, or wondering what class your rig fits? Here's the plain-English rundown of the main RC rock-crawling and scale classes — what defines each and where to find the official rules.
Rigs running 1.9-inch (bead-lock) wheels — the most popular scale size. Judged on a blend of scale looks and real-world capability.
Dedicated competition crawlers on 2.2-inch wheels — performance first, scale looks second. Frequently 4-wheel-steer comp chassis.
Comp rigs on tires larger than the 2.2 class — the biggest wheels, most clearance and flex, for the toughest courses.
Scale trucks driven on natural trails — judged on scale realism, accessories and how well they drive, not just raw capability.
High-speed rock racing inspired by full-size Ultra4 / King of the Hammers — machines that both crawl obstacles and race between them.
Small-scale crawlers (typically 1/18 to 1/24) built and driven on tabletop, backyard and indoor courses.
Class names and their tire sizes are well established, but exact rules (tire diameter, wheelbase, motor limits, gate widths) vary by sanctioning body and event — always check your club's or series' current rulebook.