There are a few conditions that may cause this issue. First, check to make sure that the engine you're using is recommended for your model of  Inflatable Boat. The next step is to check your propeller. Are you using a stock propeller? Often stock propellers are too dull on the leading edge and are designed for V-hulled boats. Due to the climbing demand for catameran hulls, propellers have become an issue. Often this issue can be resolved by sharpening the propeller along the leading edge and adding cup.

We recommend you take your propeller to your local shop and and have the leading edge sharpened and cupped.  If your local propeller shop is unable to fill your needs, contact us.