1. What is an RC Gear Ratio Top Speed Calculator?

Definition: This calculator estimates the top speed of an RC vehicle based on motor specifications and gear ratio.

Purpose: It helps RC enthusiasts optimize their vehicle's performance by calculating theoretical top speed with different gear ratios.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( TS \) — Top speed (mph)
• \( MaxRPM \) — Motor's maximum RPM
• \( KV \) — Motor KV rating (RPM per volt)
• \( Voltage \) — Battery voltage
• \( GR \) — Gear ratio (unitless)
• \( constants \) — Wheel circumference and efficiency factors

Explanation: The formula calculates the motor's RPM under load, then converts this to vehicle speed considering the gear reduction and wheel size.

3. Importance of Gear Ratio Calculation

Details: Proper gear ratio selection balances speed and torque, prevents motor overheating, and maximizes battery life.

4. Using the Calculator

Tips: Enter your motor's Max RPM and KV rating, battery voltage, and gear ratio. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is KV in RC motors?
A: KV represents how many RPM the motor turns per volt applied (no load). Higher KV means higher RPM but typically lower torque.

Q2: How do I find my motor's Max RPM?
A: Max RPM is approximately KV × Voltage, but check your motor specifications for exact values.

Q3: What's a typical gear ratio for RC cars?
A: This varies widely (3:1 to 10:1 common) depending on vehicle type, motor, and intended use.

Q4: Why is my actual speed lower than calculated?
A: Real-world factors like friction, air resistance, voltage sag, and motor efficiency reduce actual speed.

Q5: How does wheel size affect top speed?
A: Larger wheels increase top speed but require more torque. The calculator includes wheel circumference in its constants.