---
product_id: 521533048
title: "12T/22T Overdrive & 24T/10T Underdrive Steel Helical Gear for TRX4M"
brand: "injora"
price: "174.52 DT"
currency: TND
in_stock: true
category: "Injora"
url: https://www.desertcart.tn/products/521533048-12t-22t-overdrive-and-24t-10t-underdrive-steel-helical-gear
store_origin: TN
region: Tunisia
---

# Reduced vibration & noise CNC machined 20CrMo alloy steel 9% overdrive front, 16.7% underdrive rear 12T/22T Overdrive & 24T/10T Underdrive Steel Helical Gear for TRX4M

**Brand:** injora
**Price:** 174.52 DT
**Availability:** ✅ In Stock

## Summary

> ⚡ Upgrade your crawl game with precision and power!

## Quick Answers

- **What is this?** 12T/22T Overdrive & 24T/10T Underdrive Steel Helical Gear for TRX4M by injora
- **How much does it cost?** 174.52 DT with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/521533048-12t-22t-overdrive-and-24t-10t-underdrive-steel-helical-gear)

## Best For

- injora enthusiasts

## Why This Product

- Trusted injora brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Silent Strength:** Helical gear design drastically cuts down noise and vibration for a premium driving experience.
- • **Built to Outlast:** Alloy steel construction resists wear far better than stock plastic gears, keeping you ahead of the pack.
- • **Terrain Mastery Upgrade:** Optimized overdrive and underdrive ratios boost crawling and steering on complex terrains.
- • **Plug & Play Installation:** Easy fitment for TRX4M front or rear axles—upgrade your RC crawler in minutes.
- • **Precision Engineered Power:** CNC machined alloy steel ensures unmatched durability and smooth performance.

## Overview

This 12T/22T overdrive and 24T/10T underdrive helical gear set is CNC machined from durable 20CrMo alloy steel, designed to replace stock plastic gears on TRX4M 1/18 RC crawler cars. It reduces noise and vibration while providing a 9% overdrive to the front axle and a 16.7% underdrive to the rear axle, enhancing steering and crawling performance on challenging terrains. Easy to install, this upgrade is recommended for users aged 14 and above.

## Description

desertcart.com: INJORA 12T/22T Overdrive & 24T/10T Underdrive Steel Helical Gear for TRX4M : Toys & Games

## Features

- Compatible with INJORA Ascent-18 APEX Planet Portal Axles, TRX4M stock Axles, INJORA TRX4M Axles.
- CNC machined 20CrMo alloy steel gears, the vibration, noise, wear all less than stock gears.
- Helical gears offer greater strength and smooth operation than the factory spur gears.
- Less vibration, less noise, less wear then stock gears.
- Using this steel gear set will allow for a 9% overdrive to the front axle and a 16.7% underdrive to the rear axle.
- AGE RECOMMENDATION: Not for children under 14 years.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0BZLBWSRV |
| Age Range Description | Kid |
| Best Sellers Rank | #101,911 in Toys & Games ( See Top 100 in Toys & Games ) #45 in RC Vehicle Transmission Gears |
| Brand Name | INJORA |
| Color | Black |
| Customer Reviews | 4.4 out of 5 stars 214 Reviews |
| Educational Objective | Game, play |
| Item Dimensions | 3.9 x 0.79 x 2.8 inches |
| Item Weight | 0.02 kg |
| Manufacturer | INJORA |
| Manufacturer Part Number | 4M-10-34B |
| Manufacturer recommended age | 0 - 5 years |
| Material Type | Steel |
| Model Number | 4M-10-34B |
| Number of Players | 1 |
| Operation Mode | Manual |
| Set Name | Overdrive & Underdrive Gear Set |
| Size | 12/22T&10/24T |
| Theme | Car |
| Unit Count | 2 Count |

## Images

![12T/22T Overdrive & 24T/10T Underdrive Steel Helical Gear for TRX4M - Image 1](https://m.media-amazon.com/images/I/51QCuNGz2XL.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: I'm not understanding how these work. Wouldn't changing the front and rear gear ratios just cause the truck to bind?**
A: Good question. If you were to drastically change the front and rear ratio (super overdrive front and rear), it would cause issues but not bind.

The slight increase spin of the front tires causes the truck to pull more front the front, instead of push more from the rear. 

This is very helpful when going over obstacles and on hill climbing

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.tn/products/521533048-12t-22t-overdrive-and-24t-10t-underdrive-steel-helical-gear](https://www.desertcart.tn/products/521533048-12t-22t-overdrive-and-24t-10t-underdrive-steel-helical-gear)

---

*Product available on Desertcart Tunisia*
*Store origin: TN*
*Last updated: 2026-11-02*