Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: New Yamaha 90 on a 17 Super Sport Limited
Posted by gofishrob on 08/14/11 - 4:04 PM
#1
I just ordered a 90 HP Yamaha two stroke for my 1987 Super Sport Limited 17. Any thoughts on what pitch prop to bolt on and what my top end speed will be? The new motor will be on Bob's jack plate with a four inch set back.
Fyi, it took me eight months to find that motor new-in-the-crate. I hope it's the perfect choice for my Whaler.
Edited by Tom W Clark on 08/14/11 - 4:20 PM
Posted by Jack Jordan on 08/14/11 - 4:15 PM
#2
I put a leftover 90TLR, built in '08, new in the crate, on my 1963 model 16'. Ran 1400 miles up the East coast with a Solas 13.25 x 17". My top speed is 38 mph, gps and 4800 rpm.
Tom Clark is the prop guru here, I recomend going with what he says.
Posted by Tom W Clark on 08/14/11 - 4:22 PM
#3
You'll want a 13-1/4" x 15" Stiletto Advantage 4.25 or a 13-1/4" x 16" Yamaha Performance Series 3 Blade.
They are essentially the same prop, though the Stiletto uses any square-bore hub kit like the Flo-Torq.
Top speed should be 40-42 MPH.
Posted by Phil T on 08/14/11 - 5:08 PM
#4
You want to mount the motor at least two holes up.
Posted by gofishrob on 08/14/11 - 5:17 PM
#5
I only have a 40 hp on the transom now with an alumium prop and it runs 24 mph, I had hopes that the 90 would put me in the mid to high 40 s.
Posted by Tom W Clark on 08/14/11 - 9:22 PM
#6
The Yamaha 90 HP two stroke will not put you in the mid to high 40's.
Posted by gofishrob on 09/10/11 - 9:05 PM
#7
Jack sounds like your not proped correctky with 4800 rpms at top speed and Tom what rpms can be expected with your set set up? I ran the boat today for the first time since the new motor install , 17 yamaha prop only gave me 4400 rpms at 33 Mph , not good!
Posted by John Fyke on 09/11/11 - 5:06 AM
#8
As Phil said you want the motor at least two holes up. How is yours mounted? It makes a huge difference with performance.
Posted by Jack Jordan on 09/11/11 - 5:51 AM
#9
I ran the boat today for the first time since the new motor install , 17 yamaha prop only gave me 4400 rpms at 33 Mph , not good!
Sounds like the Yamaha prop takes more power to turn than my Solas. I plan to follow Tom's advice and get the Stiletto 15 or Yamaha 16 very soon.
As Phil and John say, mount that motor at least 2 holes up and your RPM will follow. Mine is 3 holes up.
Posted by msd58 on 09/12/11 - 4:13 AM
#10
gofishrob wrote:
Jack sounds like your not propped correctly with 4800 rpms at top speed and Tom what rpms can be expected with your set set up? I ran the boat today for the first time since the new motor install , 17 Yamaha prop only gave me 4400 rpms at 33 Mph , not good!
My 90 Yamaha 2 stroke runs about 4800-4950 RPM at about 40 mph 17" pictch
Posted by gofishrob on 09/14/11 - 5:48 PM
#11
Msd58 , What Whaler are you runnig and when you say about 40 , Is that a guess or gps? Stainess or alumiun prop?
and Jack I also installed a jackplate so I can play with the motor height, New prop ny the weekend , I will post an update.
Thanks guys!
Posted by msd58 on 09/14/11 - 7:48 PM
#12
gofishrob wrote:
Msd58 , What Whaler are you running and when you say about 40 , Is that a guess or gps? Stainless or aluminum prop?
and Jack I also installed a jackplate so I can play with the motor height, New prop ny the weekend , I will post an update.
Thanks guys!
Running a 17' Montauk with a stainless prop. The prop I have was a 19" that the prop shop banged down to a 17" GPS
Posted by Tom W Clark on 09/14/11 - 9:04 PM
#13
What'a a 17" GPS?
Posted by tedious on 09/15/11 - 4:40 AM
#14
Tom W Clark wrote:
What'a a 17" GPS?
Quite expensive, and hard to fit in your console.