Axial Wraith Gearing Guide — FDR, Pinion & Spur Chart

Axial Wraith RC Gearing & Optimization Guide

Optimizing your gear ratio is one of the most effective ways to balance speed, torque, and electronics longevity in your Axial Wraith (Rock Racer). The relationship between your pinion gear (attached to the motor) and your spur gear (attached to the transmission) dictates how hard your motor has to work — and on a 1/10 rock racer & trail crawler platform with a 20.83 internal transmission ratio, even a single-tooth pinion change shifts your final drive ratio by 3-5%.

The Axial Wraith is the archetypal rock racer — a solid-axle platform designed to bridge the gap between slow-speed rock crawling and higher-speed desert running. Its internal ratio is roughly half that of an SCX10, which is why it uses higher-RPM brushed motors and brushless setups that would be badly mismatched on a dedicated crawler.

Rock Crawler & Trail Truck Drivetrain Notes for the Axial Wraith

Ultra-low speed crawling on a Axial Wraith demands heavy grease packed into the portal or straight axles to damp shock loading and keep the ring-and-pinion quiet under sustained torque. Whether you are running a precisely tuned slipper clutch or a fully locked differential, the goal is to make the drivetrain deliver torque smoothly instead of shock-loading it into a rock face. High-torque binds against a ledge can spike amp draw well past continuous ratings and overheat the motor even at walking pace, so a small in-line wattmeter or an ESC with current logging is worth more than another temperature reading — heat shows up long after the damage is already done.

🛠️ Essential Tools Required for Gearing Changes

Hex drivers (1.5mm, 2.0mm, or 2.5mm depending on the Axial Wraith variant)
Paper strip (for setting precise gear mesh)
Infrared temperature gun (crucial for monitoring motor heat after each run)
Threadlock (for the pinion gear grub screw)
Pinion gear puller (recommended when swapping gears on a hot motor shaft)

📋 Comprehensive Gearing & Temperature Guide

1. Understanding Pinion vs. Spur Gear Adjustment

Changing your gears alters your final drive ratio. Installing a larger pinion gear or a smaller spur gear increases top-end speed but increases the load on the motor, causing it to run hotter. Conversely, a smaller pinion or larger spur increases torque and acceleration while lowering top speeds and keeping your motor cool. On the Axial Wraith, this trade-off is amplified by the fixed 20.83 internal ratio — small external changes have a direct thermal consequence.

2. How to Set a Perfect Gear Mesh

Improper gear mesh will quickly strip your spur gear or bind your drivetrain.

Loosen the motor mount screws slightly.
Place a small strip of standard notebook paper between the pinion and spur gear teeth.
Press the gears tightly together and tighten the motor mount screws.
Roll the paper out. The paper should have clean, crisp crinkles without ripping.

Recommended Pinion & Spur Chart

All combinations use a 56T 48-pitch spur. FDR is calculated as (spur ÷ pinion) × 20.83 internal ratio.

Pinion	Spur	FDR	Typical Use
12T	56T	97.21	High-bite carpet / tight indoor
14T	56T	83.32	High-bite carpet / tight indoor
16T	56T	72.91	High-bite carpet / tight indoor
18T	56T	64.8	High-bite carpet / tight indoor
20T	56T	58.32	High-bite carpet / tight indoor

Understanding Pinion & Spur Gears

Stock Wraith uses a 14T 32-pitch pinion / 56T spur. Rock racers running brushless typically upgrade to 3300 Kv motors and step the pinion up to 16T-18T for higher top speeds on open desert lines.

Rollout Targets

Working Wraith rollout on stock 4.75-inch tires is around 1.0 inches per motor revolution — much taller than a pure crawler and appropriate for the 15-30 mph rock-racing envelope.

Motor Temperature Management

Because the Wraith spends more time at sustained speed than a crawler, motor temps behave more like a basher — target under 180F (82C) on brushed and under 170F (77C) on brushless.

⚠️ Critical Safety & Temperature Warning

Always use an infrared thermometer to check your motor and ESC temperatures during a run. RC electric brushless motors should never exceed 160°F (71°C). Exceeding 180°F (82°C) risks permanently demagnetizing your motor rotor and frying your Electronic Speed Controller. If your Axial Wraith is running above these thresholds, you must "gear down" by installing a smaller pinion gear immediately, improve airflow with a larger motor fan, and inspect the drivetrain for binding.

Calculate a custom FDR for your Axial Wraith

The link below opens the calculator with Custom / Other Chassis pre-selected, the Axial Wraith's internal ratio of 20.83 and its recommended battery of 3S LiPo (11.1V) already set — just plug in your pinion, spur, motor, and tire to see top speed, runtime, and FDR for your exact setup.

Open calculator with 20.83 ratio + 3S LiPo (11.1V) preset →

Axial Wraith (Rock Racer) Gearing Guide