Looking to change prop.

[sean]

115 2 stroke 2001 with an 13 1/4 x 17 -k
Would like more top end... 4000 to 4800 same speed, same feel.... Crestline 18ft 5"
What does the ( K ) stand for??
Any help would be great>>>>>>>>>>

[jonp]

Hello, The K is a series of yamaha props. They come in Black painted stainless (not sure why they paint them...) and white painted aluminum. The K series stainless is a decent prop. If you want more out of your engine you will to drop pitch. I would guess that the 115 should run between 4500 to 5500. You have a way to go if that is what your issue is.
I run a 90 HP on a 17 ft boston whaler(montauk hull) loaded up about 1800 LBS. I use a 17 inch K stainless. Top end is 5700 RPM trimmed out. You have have a heavier rig but with 115 should not be too far off from where I am running considering the extra HP.

It May be something else. Can you provide more info?

Jon

[sean]

thanks for all the good question.
Top end 5200rpm timmed out ....
Boat loaded down 2200LBS.
4800 to 5200 rpm there is 5mph gain off the gps.
The prop is white, so it is aluminum.
Have you ever see a prop slip at mid range and then gain power at top end?
Will try a friends (19ss) this weekend and see if there is a difference........

[jonp]

If you are running 5200RPM with a 17SS a 19 may drop you to 4800RPM or more. Hole shot will be sluggish. Also note that all 19SS props are not created equal. I tried 19 Michigan Rapture last year, 13 3/8 X 19 with radical blades. Way to big. Top end with a ligh load, was 4900RPM, a loss of 800 rpm. I am about to try a 19SS yamaha K. I will guess I will lose about 300 to 400, may be pick up a a little speed.

Jon