By West Marine Staff, Last Updated: 6/10/2019
The length of a slalom ski is based on the weight of the skier, and there is a pretty simple formula for figuring the correct length. Higher towing speeds are generally associated with smaller skis and/or slalom skis, while lower towing speeds usually require two skis that are longer, wider, or both. See the chart below.
For shaped skis the sizing is more general with only the lowest range of boat speeds recommended. Under 175 lb: 61"-65" and over 175 lb.: 65"-67". Source: O'Brien Product Catalog
| Weight | 26-30mph | Boat Speed 30-34mph | 34-36mph |
|---|---|---|---|
| Under 100lb. | 61"-64" | 61"-64" | 61"-64" |
| 105-120lb. | 61"-66" | 61"-64" | 61"-64" |
| 115-140lb. | 61"-66" | 61"-66" | 63-"66" |
| 135-160lb. | 64"-69" | 63"-66" | 63"-66" |
| 155-180lb. | 66"-72" | 66"-69" | 66"-69" |
| 175-200lb. | 68"-75" | 68"-72" | 66"-70" |
| 200+lb. | 70"-75" | 68"-75" | 68"-72" |