Shoulder and Elbow Angles in Bike Fitting: Reach, Stem and Arms

• Shoulder angle: the angle at the shoulder joint between the line to the hip and the upper arm (hip–shoulder–elbow). Around 90° means the upper arm is roughly at a right angle to the torso.
• Elbow angle: the angle at the elbow between the upper arm and the forearm (shoulder–elbow–wrist). 180° is a straight arm.

The ranges assume your hands are on the hoods. On the drops your elbows bend more, and on the tops they open.

Holliday and Swart (2021) measured the static joint angles cyclists choose on their own bikes. The average elbow was 19 ± 8° of flexion, about 161° as an interior angle and inside the 150–165° range.

On a TT or triathlon bike the forearms rest on the pads, so the elbow is bent far more. Those ranges are explained in TT and triathlon bike fit.

Use the same setup as for the torso angle: bike on a trainer and level, phone side-on and level at hip height 2–3 m (7–10 ft) away, hands on the hoods, riding at your normal effort. Then measure the angles by hand on the photo, or let the position check measure all three. The full setup is in how to check your cycling position at home.

Shoulder angle

• Below the range: the cockpit is likely cramped and your hands are close to your body. Consider a longer stem.
• Above the range: the position is likely stretched out. Consider a shorter stem.
• Inside the range: fine-tune by feel.

Why: with your torso where it is, moving the bars forward swings the arm away from the torso and opens the shoulder angle. Moving them back closes it.

Elbow angle

• Above the range (arms close to straight): soften your elbows a little. A slight bend helps absorb road vibration.
• Below the range (elbows tucked): ease off your grip and let your arms extend a little.
• Inside the range: no change needed.

With a wheel visible in your photo, the position check turns a shoulder angle outside the range into an approximate stem change in millimeters. The figure assumes your torso stays where it is, so it can come out large. Above about 30 mm it shows the angles only and suggests checking your frame size and reach instead.

Change the stem in small steps and ride a few times before the next change. A longer or shorter stem also moves your torso a little, so measure all three angles again afterwards. The fit constructor shows how a stem change moves your torso on your own bike’s geometry. It shows shoulder and elbow angles on aero bars only.