Specialized Aethos 2 Pro: which size fits you?

Measuring inseam

Barefoot, back against the wall, a book pulled firmly up into your crotch — then from the floor to the top of the book.

Left empty, we estimate it from your height.

Measuring arm length

Let the arm hang loosely and measure from the corner of the shoulder (the bone at the top outside) to the knuckle of the wrist. It is easier with two people.

56 fits you.

Example — enter your measurements · Specialized Aethos 2 Pro · 181 cm · Inseam estimated

you, 181 cm
49
52
54
56
58
61
155 160 165 170 175 180 185 190 195 200
  • fits
  • fits with tweaks
  • just about fits
  • fits best
  • What “fits” means

    Calculated like on the frame map, with the stem your height gets as it comes and the saddle set for your legs.

    Fits: with 0 to 2 cm of spacers above the flat cap.

    With a tweak: with more spacers, up to 4 cm.

    Tight: only with a stem shorter or longer than usual.

Finding your position

If you sit well on your bike, measure it: from the top of the saddle level forwards, then straight down to the top of the handlebar.

Race bikes come with about 7 cm, endurance bikes with about 5 cm, trekking bikes with the bar at saddle height.

If you can't reach your toes with straight legs, set it more upright. When in doubt, too: lower is easy later with fewer spacers, higher often isn't.

Stretched like on a race bike. Fast, takes flexibility in the hips and back.

On the bike that means: Bar 6.5 cm below the saddle

Specialized Aethos 2 Pro 54: you on this size

54 with tweaks

Back 43°

Compared with 56: Handlebar 7 mm closer, 21 mm lower

Open 54 in the calculator with your measurements →

Specialized Aethos 2 Pro 56: you on this size

56 fits

Back 44°

Compared with 54: Handlebar 7 mm farther away, 21 mm higher

Open 56 in the calculator with your measurements →

Frame map →

Where the numbers come from