RC Ackermann Steering Explained
What is Ackermann?
Ackermann refers to the difference in steering angle between the front tires as the car turns. A low Ackermann setting will have both tires angles closer together, while a high Ackermann setting with set the tires with more angle difference.
When your RC car enters a corner with a higher Ackermann angle:
• The inside front tire turns sharper
• The outside front tire turns less
This allows both tires to follow their natural arc through the corner without dragging or scrubbing excessively.
In RC cars, Ackermann is built into the steering system geometry, which includes:
• Bellcranks
• Steering rack or Ackermann plate
• Steering arms on the hubs
A simple way to think about it:
• More Ackermann = bigger difference between left and right steering angles
• Less Ackermann = both wheels turn more evenly
Why Ackermann Matters In RC Cars
Ackermann directly affects how your car behaves in three key areas:
1. Corner Entry
It determines how quickly the front end “bites” when you turn the wheel.
2. Mid-Corner Steering
It influences how the car holds its line once it’s already in the turn.
3. Steering Feel
It changes how smooth or aggressive the car feels when transitioning into corners.
If your setup is close but something still feels off, Ackermann is often the fine adjustment that brings everything together.
How Ackermann Affects Handling
Turn-In Response
More Ackermann
• Faster, sharper turn-in
• More responsive front end
Less Ackermann
• Smoother, slower turn-in
• Easier to control at speed
Mid-Corner Behavior
More Ackermann
• Can feel aggressive or inconsistent
• Inside tire works harder
Less Ackermann
• More stable and predictable
• Better for maintaining a smooth arc
High-Speed Stability
More Ackermann
• Can make the car twitchy
Less Ackermann
• Improves stability in fast sections
Tire Wear
More Ackermann
• Increased wear on the inside front tire
Less Ackermann
• More even front tire wear
How To Adjust Ackermann On An RC Car
Ackermann is adjusted by changing the position of your steering links and pivot points.
1. Ackermann Plate or Steering Rack
Most modern RC cars include multiple mounting holes.
• Move the steering link closer to the centerline = More Ackermann
• Move it further outward = Less Ackermann
2. Steering Arm Position
Some hubs allow different mounting holes for the steering link.
• Inner hole = more aggressive steering (more Ackermann)
• Outer hole = smoother steering (less Ackermann)
When To Increase Ackermann
Increase Ackermann when you need more steering response.
Best for:
• Tight, technical tracks
• Hairpins and chicanes
• Low-speed layouts
• Cars that feel slow to turn
What you’ll notice:
• Faster corner entry
• More front-end grip
• Quicker direction changes
Trade-offs:
• Can become twitchy
• Less stable at speed
• Increased tire wear
When To Decrease Ackermann
Decrease Ackermann when you want more control and stability.
Best for:
• High-speed tracks
• Long sweeping corners
• Loose or low-grip surfaces
• Cars that feel nervous or oversteer
What you’ll notice:
• Smoother steering
• More predictable handling
• Better high-speed control
Trade-offs:
• Slower turn-in
• Reduced steering in tight corners
Common Ackermann Mistakes
1. Using Ackermann as a First Adjustment
Ackermann should be a fine-tuning tool, not your starting point.
Always dial in:
• Camber
• Toe
• Ride height
• Shock setup
…before adjusting Ackermann. In all honesty, most of my tuning is done with without ever touching Ackermann.
2. Making Large Changes
Small changes go a long way. Jumping between extreme positions can:
• Mask other setup issues
• Make the car harder to read
3. Ignoring Track Conditions
Ackermann is highly track dependent. A setup that works on a tight indoor track may feel terrible on a large outdoor layout.
4. Overlooking Tire Wear
If your inside front tire is wearing out quickly, Ackermann may be too aggressive.
What to Check After Changing Ackermann
Whenever you change Ackermann, double-check the rest of your front-end setup.
Toe Angle
• More Ackermann + toe-out = very aggressive steering
• You may need to reduce toe-out
Camber
• More Ackermann increases load on the inside tire
• Adjust camber to maintain a good contact patch
Steering Dual Rate
• High Ackermann can feel too sensitive
• Lower dual rate to smooth steering input
Front Roll Center
• High roll center + high Ackermann = aggressive front end
• Lower roll center if needed for balance
Front Differential (4WD)
• Ackermann changes how power is applied through the front tires
• Adjust diff fluid if the front end feels too strong or too weak
Servo Speed
• Fast servo + aggressive Ackermann = twitchy feel
• Slowing the servo can improve control
Tires
• Softer tires increase the effect of Ackermann
• Harder tires can help calm the car down
Bump Steer
• Changing steering geometry can affect bump steer
• Make sure your steering links are still properly aligned
A good approach:
1. Set baseline
2. Increase Ackermann slightly
3. Test
4. Decide if the car improved or became harder to drive
FAQ
Q: What is Ackermann in simple terms?
A: It’s the difference in steering angle between the inside and outside front wheels when your car turns.
Q: Does more Ackermann mean more steering?
A: Not exactly. It changes how the steering is applied, especially during corner entry.
Q: Is more Ackermann always better?
A: No. It helps in tight corners but can hurt stability at high speed.
Q: How do I know if I need less Ackermann?
A: If your car feels twitchy, inconsistent or unstable in fast corners, try reducing it.
Q: Can beginners adjust Ackermann?
A: Yes, but start small. It’s best used after your basic setup is already dialed in.
Q: Does Ackermann affect 2WD and 4WD the same way?
A: The concept is the same, but 4WD cars may react more aggressively due to front drive pulling the car through corners.
Related Tuning Adjustments
To get the most out of this setup change, review these related guides:
• Axles – Inline and Trailing
• Steering Throw Symmetry
• Toe In / Toe Out
Back to the RC Suspension Tuning Guide.
