Hi folks. I have a 2006 2120SC with a F150. The boat came with a 141/4 by 16 polished ss prop. I checked the Yamaha performance bulletins and found that they had tested the boat in June 2003 but with a 133/4 by 17 prop. Results at 4500 rpm were 30.4mph and 3.75 mpg.....not bad.
I called Jeff at Parker and learned that they are now using the 141/4 by 16 prop on that boat. Apparently it wasn't available in earlier years. Jeff was kind enough to send me the Yamaha test bulletin he had. I guess everthing doesn't appear on the Yamaha site.
I was expecting to see better performance. No way. In fact the performance was much worse. At 4500rpm speed was 29.6 mph but only 3.02 mpg. Best mpg was 3.28 at 4000 rpm at 25.6 mph. This is about 25% more consumption at 30mph. Similar results were noted at other rpms. Top speed essentially the same.
Weight of boats were almost identical as was wind. The only difference was water and air temperature......75F and 85F for the June test with the 133/4 and 48F and 38F for the Feb test. Can't believe that explains it.
Sent Jeff an Email asking what is going on. Hope to hear from him. With the cost of gas a correct prop will quickly pay for itself.
Any comments greatly appreciated.
Thanks in advance.
Ray
I called Jeff at Parker and learned that they are now using the 141/4 by 16 prop on that boat. Apparently it wasn't available in earlier years. Jeff was kind enough to send me the Yamaha test bulletin he had. I guess everthing doesn't appear on the Yamaha site.
I was expecting to see better performance. No way. In fact the performance was much worse. At 4500rpm speed was 29.6 mph but only 3.02 mpg. Best mpg was 3.28 at 4000 rpm at 25.6 mph. This is about 25% more consumption at 30mph. Similar results were noted at other rpms. Top speed essentially the same.
Weight of boats were almost identical as was wind. The only difference was water and air temperature......75F and 85F for the June test with the 133/4 and 48F and 38F for the Feb test. Can't believe that explains it.
Sent Jeff an Email asking what is going on. Hope to hear from him. With the cost of gas a correct prop will quickly pay for itself.
Any comments greatly appreciated.
Thanks in advance.
Ray