What Is Dual Rate on an RC Car? Steering Rate, Throttle Rate and Expo
Dual rate is a transmitter setting that limits how far a channel moves when you turn the wheel or pull the trigger all the way. On RC cars it’s mostly used for steering: at 100% the wheels turn their full amount; at 70% they only turn 70% as far, which makes the car easier to control at speed and less likely to spin or roll. It’s usually a knob or switch on the transmitter, so you can change it while driving. Some radios also offer throttle dual rate to limit power.
By Kyle HilsonUpdated: October 20264 min read
Dual rate vs end points vs expo
| Setting | What it does | When to use |
|---|---|---|
| Dual rate (D/R) | Scales the total travel at full input | Make steering calmer at speed |
| End points (EPA/ATV) | Sets the maximum travel each side so the servo doesn’t bind | Setup, protect the servo |
| Expo | Softens response near centre, keeps full travel at the ends | Fine control around straight-ahead |
How to set it
- First set the steering end points so the wheels reach full lock without the servo straining.
- Drive with dual rate at 100% and notice whether the car is twitchy at speed.
- Reduce dual rate in steps (e.g. to 80–90%) until the car feels controllable.
- Check you still have enough steering for tight corners.
- Note the setting for different surfaces: less on high-grip pavement, more on loose dirt.
When dual rate helps
Dual rate is most useful when the car turns too sharply, especially on high-grip surfaces where full lock can make it flip, and for beginners who over-steer. Racers often adjust it during a race as tyres wear or the track changes. Lowering steering rate also reduces scrubbing at high speed, which helps keep momentum. Transmitter basics are explained in how to control an RC car.
Throttle dual rate
Some radios have throttle dual rate or a throttle limit, which caps forward power. It’s useful for teaching kids, for driving in small spaces, or for slippery conditions. Some ESCs have a training mode that does the same; using the radio setting lets you change it without reprogramming the ESC.
Dual rate in planes and helicopters
In aircraft radios, dual rates usually sit on switches for each axis, letting pilots fly gentle low rates for normal flying and high rates for aerobatics. The idea is the same: scale how far the surfaces move at full stick. Radio types and features are covered in types of RC controllers.
Tips
- Never use dual rate to fix binding; adjust end points instead.
- Combine a little expo with dual rate for smooth, precise steering.
- Recheck trims after changing rates.
- Write down good settings for each car and surface.
An example
Imagine a 1/10 touring car on a high-grip carpet track. At 100% steering, it turns sharply enough to grip-roll in tight corners. Dropping dual rate to 80% reduces the maximum wheel angle so the car can’t turn hard enough to roll, while still making the hairpin. On a loose outdoor dirt track, the same car may need 100% to turn at all, so the driver turns the dual rate back up. That flexibility is why dual rate is on almost every hobby transmitter.
For beginners
Beginners tend to make large steering inputs. Setting dual rate lower calms the car down and makes it easier to drive straight and smooth. As skills improve, increase it gradually.
FAQ
What does D/R mean on an RC remote?
Dual rate: it limits how far a channel moves at full input.
Should dual rate be 100%?
Only if you want full steering; many drivers use 70–90%.
Is dual rate the same as expo?
No, expo changes the feel around centre; dual rate scales the total travel.
Can dual rate limit speed?
Throttle dual rate or throttle limit can, on radios that have it.
More on this topic: the complete RC Cars guide covers the basics behind this article.
About 20 years in RC. Mostly boats in the NAVIGA Mini Eco Expert class, with many self-made parts; also a King Motor Baja 5B, a home-built electric plane, home-built nitro planes he has flown, and an RC helicopter. More about SwellRC
