RC Wheel, Rim, and Tire Fitment Guide

How RC Wheel Fitment Works

RC wheel fitment depends on three things working together: the tire bead size (how big the tire opening is), the rim type (standard, beadlock, or stepped), and the hex driver size (the square peg on your axle that the wheel slots onto). Getting any one of these wrong means the wheel won't mount, or won't stay on. Use the table below to match your platform before you buy.

Fitment Compatibility Table

Tire Bead Size Rim Type Hex Size Common Platforms Notes / Adapters
1" (micro) Standard injection-moulded ~7 mm (proprietary) Axial SCX24 Wheel hole and axle are platform-specific; aftermarket options are limited. See: JConcepts Hazard SCX24 1" Wheel Black 4pc
1.55" Standard or beadlock 12 mm 1/24–1/18 crawlers, Redcat Ascent-18 Narrow rim for tight-clearance rigs. Verify your axle hex before ordering. See: RC4WD 1.55" Rocky Country Advanced X3 Tires
1.7" Standard or beadlock 12 mm 1/18 crawlers, some comp-spec rigs Common on smaller-scale competition crawlers. See: RC4WD 1.7" Fuel Mud Gripper M/T Tires
1.9" Standard or beadlock 12 mm Axial SCX10 series, Traxxas TRX-4, most 1/10 crawlers The most common crawler size. Works with a wide range of 12 mm hex rims. TRX-4M (1/18) uses a smaller proprietary hex — a stepped hex adapter is required to run standard 12 mm wheels. See: Pro-Line 1.9" Interco Super Swamper XL G8 Tires | Pro-Line Mickey Thompson 1.9" Predator Tires | Pro-Line 1.9" Dual Stage Foam Inserts (2)
2.2" Standard or beadlock 12 mm or 17 mm 1/10 monster trucks, short course trucks, some crawlers Verify hex size for your specific truck — Arrma and Traxxas 2.2" rims often differ. 12 mm hex is typical on crawlers; 17 mm is common on Arrma bashers and Traxxas MT/SCT. See: Pro-Line Street Fighter 2.2"/3.0" Tires on Rem Hex Wheels | Louise R/C CR-Griffin 2.2" 12mm Hex on Black Wheels | Pro-Line Hoosier 2.2" Front Tires
2.8" Standard 12 mm or 17 mm Traxxas Stampede 4x4, Rustler 4x4, LaTrax Traxxas 2.8" wheels use a 12 mm hex (rear on some variants) or 17 mm — check your truck's axle. See: Traxxas Anaconda Wheels & Tires 2.8" | Traxxas Sledgehammer 2.8" Belted Tires | Traxxas Wheel Hubs, Hex (2)
3.0" (SCT) Standard / Short Course 17 mm (rear), 12 mm (front) Traxxas Slash 4x4, Arrma Senton, Losi TEN-SCT Short course trucks typically use different hex sizes front and rear. Confirm front/rear before ordering. See: Traxxas SCT Tire & Wheel Assy (orange beadlock) | Traxxas SCT Tires & Wheels, assembled glued | Pro-Line Bald Eagle 2.2"/3.0" MC Tires
6.8" OD (MT 6S) Standard 17 mm Arrma Kraton 6S, Notorious 6S, Outcast 6S Large-scale bashers use 17 mm hex as standard. Do not pair with 12 mm hex rims without an adapter. See: Arrma Backflip MT 6S Tire, 17mm Hex, Black Wheels

Hex Size Quick Reference

Hex Size Typical Use Key Products
12 mm 1/10 crawlers, some MTs and SCTs, Arrma Typhon Grom Arrma 12mm Wheel Hex Set (Metal) 4pc | Arrma Metal Axle & Wheel Hex Set B – GROM | Pro-Line VW Bug Kit + Flat Iron Tires 12mm for Arrma Typhon Grom
17 mm 1/10 scale bashers, 6S monster trucks, Traxxas SCT rear Traxxas 17mm Splined Wheel Nuts (black-anodized) (4)
Stepped hex Adapter to run larger-hex wheels on smaller-hex axles (e.g., TRX-4M) See notes in the table above — contact us if you need help sourcing a stepped hex adapter for your platform.

Tire Glue & Accessories

Whether you're mounting crawler tires to beadlock rims or gluing foam-backed rubber to standard rims, a quality CA glue makes the difference between a tire that stays on and one that debeads mid-run.

Frequently Asked Questions

What's the difference between 12 mm and 17 mm hex?

The hex refers to the size of the drive interface between your axle and the wheel. A 12 mm hex has a 12 mm flat-to-flat measurement; a 17 mm hex is larger. They are not interchangeable without an adapter. Most 1/10 crawlers use 12 mm; most 1/10 bashers and 6S trucks use 17 mm.

What is a stepped hex adapter?

A stepped hex adapter (also called a hex riser or hex spacer) has a different hex size on each end — for example, it accepts a vehicle's smaller axle hex on the inside and presents a larger hex on the outside. This lets you run wheels designed for a different hex size. The most common use case at this scale is running standard 12 mm hex wheels on the Traxxas TRX-4M, which ships with a smaller proprietary hex.

What does "wheel hole vs. axle fit" mean?

Wheel hole refers to the opening in the center of the wheel that the hex driver passes through. Axle fit refers to how the wheel seats on the axle stub itself. On some platforms (especially micro-scale and proprietary systems like the SCX24 or TRX-4M), the axle diameter matters separately from the hex size. If the wheel hole is too small, the wheel won't slide onto the axle at all.

Can I run 1.9" tires on my TRX-4M?

The TRX-4M ships with a smaller proprietary hex. To run standard 1.9" wheels intended for a 12 mm hex, you will need a stepped hex adapter. Verify the adapter is available for your specific axle before purchasing tires or rims. We recommend confirming fitment with us before ordering — contact us here.

Are all Arrma trucks 17 mm hex?

No. Arrma's 6S-class trucks (Kraton 6S, Notorious 6S, Outcast 6S) use a 17 mm hex. Some smaller Arrma models — including the Typhon Grom and GROM — use a 12 mm hex. Always check your specific model's manual or the product listing before ordering. See the Arrma 12mm Wheel Hex Set for 12 mm platforms.

Fitment information on this page reflects verified in-stock products as of the page's last update. Compatibility details are specific to the products and platforms listed — do not assume universal compatibility across all vehicles or brands. If you're unsure, contact us before you buy.