MOTOR
To select the motor best suited for a hull it is important to know the hull size and amount of cell planned to be used. Size of hull will determine the size of motor needed to push the weight. Cell count will determine the wind (Kv) of motor needed.

Hulls from 20”/55cm – 34”/86cm typically will use a 540 size motor 36mm Diameter by 50-75mm length

Hulls from 34”/86cm – 40”/102cm + typically will use a motor with a diameter around or over 42mm and a length of over 60mm.

To determine the best suited Kv for a motor, the cell count planned to be used is needed. Following this chart will provide a wide-ranging base for proper kv selection.


2 cell LiPo > 3000-5500Kv
3 cell LiPo > 2000-3500kv
4 cell LiPo > 1350-2700Kv
6 cell LiPo > 900-1800Kv
8 cell LiPo > 675-1350Kv
10 cell LiPo > 550-1100Kv
12 cell LiPo > 450-900Kv

This is loosely based on an RPM range. This range is approximately 20 000RPM – 40 000RPM where approximately 30 000RPM is a decent standard for nearly all boat types. Anything higher than 40 000RPM may be considered to be a SAW(Straight-A-Way) setup and will not be covered here.

A mono hull will run the Kv’s listed on the lower end of the range. (Larger Prop)
An outrigger type hull will run the Kv’s listed on the higher end of the range. (Smaller Prop)

Higher Quality motors will run higher Kv within the range listed.
Lower Quality motors will run lower kv within the range listed.