How to film yourself for an accurate bike fit analysis

Any video-based bike fit analysis — ours or anyone else's — is only as good as the footage it receives. The same bike setup, filmed under different conditions, can produce measured angles that differ by several degrees. The good news: every source of error can be controlled with a simple protocol that takes about 10 minutes. The even better news: once you film in a standardized way, your before/after comparisons become genuinely valid.

Setup (once per session)

1. Bike on a trainer, on a level surface. The front wheel (or its riser block) must sit level with the rear axle — a random book under the front wheel tilts the whole bike and shifts your back angle by 1–2 degrees. Check with a spirit level or your phone's level app placed on the top tube.

2. Camera completely fixed — never handheld. Position the phone in landscape orientation: 2.5–3 meters (8–10 ft) from the bike, roughly at your hip level when seated, perpendicular to the plane of the bike — the camera looks straight at your side. The entire rider and both wheels must fit in the frame with some margin.

Have a tripod? Great — it's the most convenient option. Don't have one? You don't strictly need it: any solution that keeps the phone completely still works just as well — leaned against a stable object (a wall, a speaker, a heavy vase) on a table, shelf or chair back, raised to the right height with a few books or a box; or a desk stand / car phone holder placed on a support at the correct height. The test is simple: once you hit REC, nobody and nothing touches the phone until you're done. The one option that doesn't work is having someone hold the phone — even the steadiest hand moves enough to corrupt the measurements.

3. Tight-fitting clothing, contrasting with the background. Form-fitting kit, in a color that contrasts with the wall behind you: dark kit against a light background or vice versa. Loose clothing is the number one enemy of detection — a flapping T-shirt hides your hip and knee.

4. Even lighting, no backlight. No window or strong light source behind you from the camera's perspective.

5. Wheel fully visible. Together with the crank length, it is the reference that makes the millimeter conversion of the measurements possible — so recommendations can tell you "lower the saddle 4–6 mm" instead of just "lower it a bit."

The recording itself

6. Warm up for 3–5 minutes before you hit REC. The step almost everyone skips — and the one that distorts results the most. During the first minutes, your pelvis is still settling on the saddle; a "cold" recording captures a position you don't actually ride in.

7. Steady cadence, 85–90 rpm, moderate resistance. Ankle angle — and through it, knee angle — varies systematically with cadence and effort. Comparable recordings are made at the same cadence and load.

8. Hands in a defined position — the same one every time. Hand position changes your back angle by 5–10 degrees, so comparing a "hoods" recording with a "drops" recording is meaningless. The app explicitly asks for your hand position with every upload.

9. Look ahead, ride naturally. Don't look at the camera, don't look down at the screen. Pedal like you do on the road.

10. Record 20–30 seconds. At 90 rpm, that's 30–45 complete pedal revolutions — enough cycles for a statistically stable value rather than a snapshot. More than 30 seconds adds no meaningful precision.

Quick checklist (save this)

• Bike level on the trainer, checked with a spirit level
• Phone completely fixed (tripod or improvised stable support), landscape, 2.5–3 m, hip height, perpendicular
• Entire rider + both wheels in frame; rear wheel clearly visible
• Tight kit, contrast with the background, no backlight
• 3–5 minute warm-up
• Steady cadence ~85–90 rpm, moderate resistance
• Hands in the declared position (same on re-recording)
• 20–30 seconds of natural pedaling

FAQ

The reference version of this guide, used by the app: the standardized filming protocol.