Re: Just a Question
Hi Jobay<br /><br />If I can add to JB's correct explaination - there is usually no linear relationship between throttle and RPM in any engine which is under load and accelerating. What you have described as happening when you shift your throttle lever is normal.<br /><br />Imagine that your boat is stopped in the water, you then shift into gear and push the throttle to a set fixed position. The following things happen in sequence;<br /><br />1. Initially the motor has to shift the boat from stopped to moving slowly. This is hard work, so the revs are lower.<br /><br />2. As the boat starts to move, it becomes easier on the motor, so the revs build up. The boat's hull will now be in displacement mode (not planing). <br /><br />3. The speed will gradually increase in displacement and so will the revs of the motor.<br /><br />4. You then reach the hull's maximum displacement speed. At this point your engine will need to keep pushing harder and harder - without any noticable increase in boat speed, until it can pop it into planing mode.<br /><br />5. Once in planing mode, the hull operates more efficiently (not having to shunt so much water around) and so the boat speed increases more rapidly and motor revs also increase rapidly.<br /><br />6. Eventually your boat speed and RPMs settle into a fixed level and stay there.<br /><br />All of the above happens with the throttle in a single fixed position. I know exactly what you are saying about the throttle lever and RPMs and have often found myself wishing there was an RPM lever too...
