Your quad flips fast but bounces at the end of every roll. You drop D gain, and the bounce softens — but now the quad feels loose and floaty on sharp stick inputs. This is the classic P-I-D tradeoff loop that feed forward was designed to break. Feed forward adds a direct stick-to-motor pathway that bypasses the PID error loop entirely, giving you immediate motor response to stick movement without waiting for the gyro to detect an error.
What Feed Forward Actually Does
In a standard PID loop, the stick position is compared to the gyro rate to produce an error, and that error drives the PID output. There is always a delay — the stick moves, the PID loop waits for the gyro to report that the quad is not yet rotating at the target rate, and only then does it ramp up motor output. That delay is milliseconds, but at 8 kHz loop rates with fast stick movements, it is enough to cause an initial undershoot followed by an overshoot as the I-term catches up.
Feed forward injects motor output directly proportional to the rate of stick movement. When you slam the stick from center to full deflection, feed forward sees the stick velocity and sends motor output before the gyro detects that the quad has not yet responded. The P and D terms still handle the steady-state tracking and damping, but feed forward handles the initial punch.
The result: the quad starts rotating the instant you move the stick, with no ramp-up delay. On a well-tuned feed forward setup, the gyro trace follows the stick trace with almost no lag — and crucially, no overshoot at the end of the move.
Feed Forward Parameters in Betaflight 4.5+
Betaflight 4.5 consolidated the feed forward settings into two primary sliders per axis:
| Parameter | Range | Default | Effect | Tuning Direction |
|---|---|---|---|---|
| Feed Forward Transition | 0.0 – 1.0 | 0.25 | How aggressively the FF ramps in at stick center | Higher = sharper center-stick feel |
| Feed Forward Boost | 0 – 100 | 20 (pitch/roll) | Additional FF at high stick deflection | Higher = more punch on full-deflection moves |
| Feed Forward Max Rate Limit | 0 – 2000 | 500 deg/s | Caps FF above this stick deflection rate | Lower = limits FF on very fast stick flicks |
Feed Forward Transition controls the shape of the FF curve near center stick. At 0.0, feed forward engages linearly from the first stick movement — this gives the most direct feel but can make the quad twitchy in a hover. At 1.0, feed forward is delayed until the stick moves past a threshold — smoother hover, less responsive on small corrections. For freestyle, 0.2-0.3 is the sweet spot. For racing on tight technical tracks, 0.1 gives the fastest initial response.
Feed Forward Boost adds an extra kick at high stick velocities. Think of it as “overdrive” for fast flips and rolls. If you do a full-deflection snap roll and the quad stops crisply without bounce, your boost is correct. If it overshoots and bounces back, reduce boost by 5-10 points. If the roll feels slow to start but finishes clean, increase boost.
Step-by-Step Feed Forward Tuning
Step 1: Baseline Your PID Tune First
Feed forward amplifies stick inputs regardless of the PID state. If your P and D are already too high, adding feed forward produces violent overshoot. Get your base tune solid with feed forward at default values before touching it. As we covered in our Betaflight RPM filtering guide, a clean gyro signal from RPM filtering is the prerequisite for any meaningful tune work.
Step 2: Set Feed Forward Transition
Fly a few punch-outs and snap rolls with Blackbox logging enabled. Open the log in Betaflight Blackbox Explorer and overlay the stick trace (rcCommand) against the gyro trace for the roll axis.
Look at the first 50 ms after a sharp stick input:
– If the gyro trace lags behind the stick trace by more than 15 ms, increase Feed Forward Transition (move toward 0.0).
– If the gyro overshoots the stick trace immediately (the quad rotates faster than commanded), decrease Feed Forward Transition (move toward 1.0) or reduce P-gain slightly.
– Ideal: the gyro trace reaches the stick target within 10-15 ms with zero overshoot.
Step 3: Dial Feed Forward Boost
Now look at the end of a fast roll — the moment the stick returns to center:
– If the gyro keeps rotating past center and then bounces back (overshoot), reduce Feed Forward Boost by 5 points. Feed forward pushed the motors too hard and the D-term could not brake fast enough.
– If the roll stops cleanly but feels slow on the initial punch, increase Boost by 5 points. The FF was too timid on the entry.
A clean feed forward tune produces a square-wave response: the gyro trace rises fast, levels at the target rate, and drops fast back to zero — all with no ringing at either transition.
Step 4: Per-Axis Tuning
Pitch, roll, and yaw have different inertias and therefore need different feed forward values. A typical 5-inch freestyle quad tunes like this:
| Axis | Transition | Boost | Notes |
|---|---|---|---|
| Roll | 0.20 | 30 | Lowest inertia, least FF needed |
| Pitch | 0.25 | 35 | Moderate inertia, front-to-back weight distribution |
| Yaw | 0.30 | 25 | Highest inertia, FF transition slightly higher to avoid yaw twitch |
Feed Forward Effect Summary
| Tuning Goal | Adjustment | Expected Result |
|---|---|---|
| Faster initial stick response | Decrease Transition | Tighter center-stick feel, possible hover jitter |
| Smoother hover stability | Increase Transition | Less twitchy hover, slower initial response |
| More punch on full-deflection flips/rolls | Increase Boost | Snappier flips, risk of bounce-back |
| Eliminate bounce at end of move | Decrease Boost | Cleaner stop, potentially softer initial hit |
| Reduce yaw twitch on throttle blips | Increase Yaw Transition | Less yaw drift during punch-outs |
Common Mistakes & What Most Pilots Get Wrong
1. Tuning feed forward before fixing mechanical issues
Feed forward amplifies the first derivative of the stick position. Any slop in your gimbal — worn potentiometers, loose tension springs — translates directly into noisy feed forward output. A RadioMaster TX16S with worn gimbals will produce micro-jitter in the stick trace that feed forward magnifies into audible motor hunting. Calibrate your gimbals and check for stick-centering precision in the Betaflight Receiver tab before tuning FF.
2. Running high feed forward with high I-term
Feed forward and I-term both produce sustained motor output — but at different times. Feed forward acts on stick movement; I-term accumulates slowly to correct steady-state error. When both are high, the quad over-responds to stick inputs and then the I-term keeps pushing in the same direction, causing a slow drift after every move. If your quad drifts after flips and rolls, reduce I-term by 5-10 points before touching feed forward.
3. Copying a pro pilot’s feed forward values
A pilot running 900 deg/s actual rates with 0.15 transition and 45 boost is flying a build with completely different inertia, motor authority, and stick technique than yours. Their values assume a specific rates profile — at 900 deg/s, the stick reaches full deflection faster, so feed forward needs less transition delay. At 600 deg/s with lower rates, the same FF values will feel dead. Tune to your rates on your build.
4. Forgetting yaw feed forward
Most pilots tune pitch and roll FF and leave yaw at default. Yaw has the highest rotational inertia and benefits the most from feed forward on sharp 180-degree turns. A well-tuned yaw FF of 25-30 boost makes snap turns feel telepathic instead of mushy. The tradeoff: too much yaw boost causes the tail to wag as the D-term fights the FF during fast yaw inputs.
⚠️ Regulatory Notice: Test flights for tuning should be conducted in accordance with the latest 2026 drone regulations in your country or region. Always verify local laws regarding flight altitude, no-fly zones, remote ID requirements, and registration before flying. Regulations vary significantly between the FAA (US), EASA (EU), CAA (UK), CAAC (China), and other authorities.
The SpeedyBee F405 V4 stack runs Betaflight 4.5 natively with full feed forward support and an ICM-42688P gyro that captures the fast stick-to-gyro response feed forward tuning demands — no gyro lag masking your FF adjustments.