BMX Crank Length Sizing Chart
The chart below can be used to estimate your proper crank arm length. Your choice of cranks may vary depending on rider style and skill level. Crank arm length is an important factor to consider with BMX racing and children's 12", 14", 16" and 18" bicycles. For adult freestyle riders the typical crank arm length will vary between 160mm up to 180mm depending on your riding style. Crank arm length is measured from the center of the spindle to the center of the pedal boss.
Many street and park riders prefer a shorter (160mm - 170mm) crank arm length. The theory behind this is that having your feet closer together allows you to jump higher. This also helps prevent the heel of your back foot from clipping your peg if you have one on that side.
| Rider Inseam | Crank Length |
|---|---|
| 20" | 140mm |
| 21" | 145mm |
| 22" | 150mm |
| 23" | 155mm |
| 24" | 160mm |
| 25" | 162mm |
| 26" | 166mm |
| 27" | 171mm |
| 28" | 175mm |
| 29" | 177mm |
| 30" | 180mm |
| 31" | 182mm |
| 32" | 185mm |
| 34" | 190mm |
Visit our TECH HELP section here for a deep dive into details, sizing, and installation instructions of each component.