By Thomas P.

Sea Quest is one of the best built and seaworthy ribs of the Greek market and is characterized by its particularly comfortable facilities and the impressive soft ride.
Being aware of the performance of the Sea Quest with the propeller of Suzuki, we wanted to see whether the Bravo I FS fits both the hull and the large (numerically) gear ratio of the Suzuki DF 225hp.

Bravo I FS 15 ¼΄΄ x 23΄΄ - Suzuki 16΄΄

The tests took place on the same day, in the same sea area, with the same loads.

Test Results

Bravo I FS 15 ¼΄΄ x 23΄΄ - Suzuki 16΄΄

Taking a look at the measurements of the above table we see that the Bravo I FS propeller:

  • needs more rpm to get the rib on plane
  • despite its longer pitch, gives us significantly lower speeds at the whole rpm range and only at WOT manages to reach the Suzuki propeller
  • shows particularly high slip numbers at the whole rpm range
  • despite its longer pitch and its additional blade, turns about 300 more rpm at WOT than the Suzuki, due to its smaller diameter and its modified characteristics
  • gives faster accelerations because it is designed to allow the engine to spin easier and faster

Regarding the behavior of the rib, the FS was holding the bow considerably higher, yet not desirable in this rib. Its grip was very good as well as the throttle response, particularly after 4000 rpm.

The setup of this engine-boat combination, in which the Suzuki 16΄΄ x 21.5΄΄ propeller reaches at 5800 rpm (rpm range at WOT is 5000-6000 for this engine) and the A / V plate is 6.5cm above the bottom of the transom, is very good and performs great at the whole rpm range.

Instead, the Bravo I FS propeller showed that it can not perform well on the particular hull with the specific engine and the measurements were very poor.

Let's keep, however, that if we ever want to switch from a 16΄΄ diameter propeller of Suzuki to a Bravo I FS one, in another engine-hull combination, we should choose an FS propeller by 4 inches longer in pitch size maintaining almost the same rpm at WOT.

Bravo I FS 15 ¼΄΄ x 23΄΄ - Suzuki 16΄΄

From the above test, it is clearly seen that «a 4-blade propeller doe’s not always mean better performance» as many boaters mistakenly believe. There are more important characteristics of a propeller than its extra blade which define whether it will perform well to a specific engine-boat combination.

There is no doubt that the Bravo I FS is a very good and cleverly designed propeller. But this does not mean that it matches with any engine-boat combination.

The Bravo I FS «doesn’t like» the heavy loads, especially when we have a single outboard on our transom and definitely «prefers» the stepped hulls.

...keep Ribbing!