Find the ideal crank arm length for your bike. Proper crank length improves pedaling efficiency, reduces knee strain, and maximizes power transfer for your body proportions.
Crank length is the distance from the center of the bottom bracket axle to the center of the pedal spindle hole. It directly affects how your legs move through each pedal stroke and influences power output, cadence, and joint stress.
Most production bikes come with 170mm or 172.5mm cranks, but this one-size-fits-most approach leaves many riders with suboptimal crank lengths. Riders with shorter or longer legs benefit significantly from properly sized cranks that match their individual biomechanics.
| Inseam Range | Approx. Height | Recommended Crank | Common Use |
|---|---|---|---|
| 65–70cm (25.5–27.5") | 152–163cm (5'0"–5'4") | 160–165mm | Short riders, youth |
| 70–76cm (27.5–30") | 163–170cm (5'4"–5'7") | 165–170mm | Average short riders |
| 76–82cm (30–32") | 170–178cm (5'7"–5'10") | 170–172.5mm | Average riders |
| 82–88cm (32–34.5") | 178–186cm (5'10"–6'1") | 172.5–175mm | Above average riders |
| 88–94cm (34.5–37") | 186–196cm (6'1"–6'5") | 175–180mm | Tall riders |
Short riders, youth, and small frames
Shorter adults and high-cadence riders
Below-average height, compact fit
Most common size, average riders
Average to above-average height
Taller riders, standard on large frames
Tall riders seeking extra leverage
Very tall riders, maximum leverage
Standard sizing based on inseam measurement.
Slightly longer for torque, but trends are shifting.
Shorter cranks for high cadence and aero positions.
When changing crank length, always re-adjust your saddle height. A longer crank effectively raises your pedal's lowest point, so raise your saddle by the same amount of change (e.g., going from 170mm to 175mm means raising the saddle 5mm).
Allow 2-3 weeks of gradual riding to adapt to a new crank length. Your muscles and pedaling neuromuscular patterns need time to adjust. Start with shorter, easier rides before returning to your normal training intensity.
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Enter your inseam measurement to get personalized crank length recommendations