Yamaha F25 (4 stroke 25 HP) propping

[junkyardwarrior]

Just picked up a new (to me) boat. 1548 War Eagle, Yamaha F25ESHY (2000 model), short shaft, tiller steering.

Working on setting it up. And (hopefully) settling a score with the local guy...

Anyway, Current RPM is 5800-5850 with a "normal" load (me, dog, tackle and supplies) and 28.1 mph max. Prop currently is a Yamaha aluminum 3x9 7/8 x 11 1/4 (from a 2 stroke 25esh)-brand new no dings and no bends. Motor is raised 2" on the transom and it will blow out if I move the load to the front unless I trim it in a couple of notches. Height can be adjusted it need be. I fish by myself most of the time. Current prop is a "little" slow to plane (but the boat is heavy so that's probably to be expected) but midrange and top end are fine for the most part. I'm on plane at about 4500 RPM (have not checked speed) and it will maintain plane down to about 4000 RPM (again, have not checked the speed).

What I am looking for is something that might give me 1-2 mph more top end. That's all I need. Looking for 30 mph, or real close. I know it might be too much to ask for but I'm willing to keep trying.

I'm looking at a Turbo Hot Shot, but not sure of which size/pitch I should be looking at. Currently a 11 1/4" pitch, should I go with a Hot Shot 11" or is that going to be a little much?

Or...if anyone has similar experiences, please share. A guy I work with says a 4 stroke won't run 30. I'm close now...and still have some left in it, at least I think so. Correct me if I am wrong?

 

[steelespike]

Re: Yamaha F25 (4 stroke 25 HP) propping

According to a 2.08 ratio 28 mph ay 5800 is about 6% slip excellent number.
If you could get 6000 with your present prop it would be 28.9.What is the write up on the Turbo hot rod?
Couldn't find a reference to a Turbo prop Turning point a suggests a 10 3/8 X 11" Don't know
if its a Hiustler or Rascal I think the Rascal is intended for a 25.
These are very effective al prop with close to ss performance.They are unpredictable however.
Stainless props can be unpredictable as well.Its hard to be sure about their affect on the hull.
At least the Turning point props are more reasonable.
Not likely to beat your present 6% slip.
While the Jon will get up on the water easy; getting speed is another issue Many jons have 4 or 5 keels
and sometimes run too flat.Also aluminum boats tend to have lots of rivets,joints and edges to add resistance.