Tonale x Colnago Y1RS seatpost

What it is:
Floor to top of the head (standing).

Why it matters:

• Used to choose frame size
• Helps scale overall geometry (stack & reach range)

What it is:
From top of pelvis/hip to shoulder (sitting upright).

Why it matters:

• Determines handlebar reach
• Influences stem length
• Comfort vs aero balance

What it is:
From crotch (pelvic floor) to ground.

Why it matters:

• Sets saddle height
• Influences crank length
• Affects knee angle & power efficiency

What it is:
Hip joint to knee (sitting).

Why it matters:

• Determines saddle setback
• Knee-over-pedal alignment
• Knee health & power delivery

What it is:
Shoulder to clenched fist (arm extended).

Why it matters:

• Determines handlebar reach
• Stem length & handlebar shape
• Aero position without overload

What it is:
From saddle (or hips) to shoulder / head (sitting).

Why it matters:

• Determines handlebar drop
• Influences:
• Stack spacers
• Bar height
• Critical for aero vs comfort balance

How this is used in real bike fitting
All measurements together define:

• Saddle height
• Saddle setback
• Frame stack & reach
• Stem length
• Handlebar drop
• Aero position sustainability

This is exactly the data needed for:

• Road
• TT
• Triathlon
• Indoor smart-trainer optimization