Lean angle

Measure motorcycle lean angle.
With your smartphone.

No extra sensor, no cloud: MotionRecord reads the motion sensors already built into your phone — and measures your lean angle instead of estimating it.

MotionRecord is a free app for iOS and Android that measures motorcycle lean angle directly via the smartphone IMU (gyroscope + accelerometer) at up to 100 Hz. Unlike GPS-based estimation (typically ±2–3°), IMU measurement achieves roughly ±0.5° accuracy — including hairpins, slow corners and areas without GPS reception.

GPS estimation vs. IMU measurement

Most apps estimate lean angle after the ride from the GPS track (corner radius + speed). That works — but has physical limits:

	GPS estimation	IMU measurement (MotionRecord)
Sampling rate	1× per second	100× per second
Accuracy	±2–3° (good reception)	±0.5°
Slow corners & hairpins	unreliable	precise
No GPS signal (forest, tunnel)	no data	keeps measuring
Principle	estimate from radius + speed	direct measurement (gyroscope)

Measured lean angle in 3 steps

1

Install the app

Get MotionRecord for free — Android on Google Play, iOS as a TestFlight beta. No account required.
2

Mount your phone rigidly

Firmly mounted beats clearly visible: vibration is the enemy of every measurement. Orientation doesn't matter — MotionRecord automatically transforms all axes into the vehicle coordinate system.
3

Start recording and ride

Start the recording, stow the phone, ride. The app runs in the background — even while you navigate with Calimoto or Komoot. After the ride: review lean angle, G-forces and elevation, or export to Kurvenfokus.

Lean angle measurement — FAQ

How accurate is smartphone lean angle measurement?

MotionRecord measures via the hardware gyroscope at up to 100 Hz and reaches roughly ±0.5° accuracy. GPS-based apps only estimate lean angle indirectly from corner radius and speed — typically ±2–3°, often worse in hairpins and slow corners.

Do I need an external lean angle sensor?

No. Modern smartphones contain a full IMU (gyroscope, accelerometer, magnetometer). MotionRecord reads these sensors directly — no external device needed.

Does the phone need a specific mounting orientation?

No. MotionRecord detects the mounting orientation automatically and transforms all readings into the vehicle coordinate system. What matters is a rigid, low-vibration mount.

Does it work without GPS reception?

Yes. Lean angle comes from the IMU, not from GPS — so it keeps working in forests, tunnels and narrow valleys. GPS only adds position and speed.

What happens to my data after recording?

Everything stays on your device — no account, no server, no forced cloud. Export as CSV, GPX or JSON, or hand the data straight to Kurvenfokus for tour analysis.

Try it for free

MotionRecord is free — Android on Google Play, iOS as a TestFlight beta.

And after the ride?

To analyze entire tours — corner by corner, with map and statistics — there is Kurvenfokus. MotionRecord records, Kurvenfokus analyzes:

kurvenfokus.de – analyze motorcycle tours ↗

Measure motorcycle lean angle.With your smartphone.