MOUNTAIN BIKE / MTB

The crotch length multiplied by 0.56 gives you the theoretical frame size of the bike

Size of the cyclist (cm) 152-162 163-168 169-174 175-178 179-182 183-188 189-200
Inseam 68-74 75-77 79-81 82-83 84-86 87-90 91-94
Bike size (in inches) 14 16 18 18.5 20 21 22
Bike size 38 41 45 46 50 52 55
Bike size XS S M M/L L L/XL XL

ROAD BIKE

The length of the crotch multiplied by 0.66 gives you the theoretical frame size of the racing bike

Size of the cyclist (cm) 150-159 159-167 167-175 175-184 184-192 192-200
Inseam 63-67 72-77 77-81 81-86 86-90 90-95
Bike size 19 19 20 21 22 23
Bike size 46 48/50 52/53 53/56 58/60 62
Bike size XS S M L XL XXL

BIKE HELMET

ROAD BIKE – MOUNTAIN BIKE
Head circumference (cm) 53-54 55-56 57-58 59-60 60 et +
Helmet size XS S M L XL