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What is Gear Ratio?
Every RC Car has two major gears to drive the car – a Pinion Gear and a Spur Gear. On battery-powered cars, the Pinion is attached to the motor and connects to the Spur, the main gear that spins the drivetrain.
On a Nitro car, the same two gears exist, however the Pinion is attached to the Clutch Bell with the Spur sitting inline with the rest of the center drivetrain.
These two gears determine your vehicle’s Gear Ratio and can be adjusted for different motor/engine types, track lengths, outdoor temperatures, etc.
There are multiple Gear Pitch types, however the different pitches do not affect the overall gear ratio.
The Gear Ratio calculation looks like this: Spur Gear ÷ Pinion Gear.
See also: Final Drive Ratio, Rollout
Tuning with Gear Ratio
Larger Pinion/Smaller Spur Gear
• More top speed
• Slower acceleration
• Less torque
• Motor/engine will run hotter
• Less efficiency, less runtime
Smaller Pinion/Larger Spur Gear
• Less top speed
• Faster acceleration
• More torque
• Motor/engine will run cooler
• More efficiency, more runtime
Back to the RC Suspension Tuning Guide.
