WELCOME TO RIVER DAVES PLACE

What prop for a 21' Baker RST?

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
I am looking for some advice on what prop to start out with on a 21' baker RST (stoker SST) the boat is equipped with a 1987 300hp Johnson outboard that has 300hrs on it. The prop that's currently on it is a 14.5 x 26 (3 blade).....I am wanting to hit speed around 80-90mph......any advice would be great thanks :)
 

Luv2gofast

Well-Known Member
Joined
Jul 1, 2011
Messages
329
Reaction score
266
I am looking for some advice on what prop to start out with on a 21' baker RST (stoker SST) the boat is equipped with a 1987 300hp Johnson outboard that has 300hrs on it. The prop that's currently on it is a 14.5 x 26 (3 blade).....I am wanting to hit speed around 80-90mph......any advice would be great thanks :)

I had a 21 RST with a 220 Merc and it always worked the best with an A5 Chopper. I ran a 26p at 72MPH but with the 300 I'm sure you could go up to a 28 or 30P. Tell me what the gear ratio is on that motor and what RPM you need to turn and I will put the numbers into my calc. I currently run a 26 Chopper II on my 20.2 Lavey with a Merc 280. I got 92MPH at 7400 RPM last weekend on lower river.
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Thanks for the info :) that really helps me. I am going to run with the standard 26 pitch i have on it now until I get a good feel for the boat (have not driven it yet). Not ready hit high speeds yet lol.. If i could hit 70 that would be fine for now. Is there a huge difference between the 26 chopper props and like a standard 26 bravo prop? I dont know the gear ratio at the moment but will let you know when i find out.....92!!! Thats really fast in 20ft boat!!! Scary!! I am new to these types of boats so i am paranoid of becoming airborne.....I guess these hulls are known to get kinda kitie :-( what river do you normally boat at? I am planning on spending most of my days at parker....maybe i will see you out there :)
 

Luv2gofast

Well-Known Member
Joined
Jul 1, 2011
Messages
329
Reaction score
266
Mostly above Havasu. I was on lower river at Twin Palms last weekend and will be at Avi in three weeks.

Just don't get too much trim in it untill you get the feel. Baker RST is a sports car, very responsive and really comes alive at about 60. You will feel it loosen up and start to dance. Much more fun to drive than my Lavey but also much more fragile. The floor (top of the tunnels) on my Lavey doesn't flex like the Baker did.

Chopper is over the hub exhuast and likes to run with the propshaft even or 1" up from the pad. Do you have a jack plate? Bravo is not a surfacing prop and likes to run in the water. It will be great for heavy loads but probably won't get the top speed you are looking for.
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Nice I should be picking my boat up in havasu this upcoming weekend.

I will try and be careful with the trim and just take baby steps to be safe :) hopefully the boat isn't too fragile because havasu and Parker get pretty choppy. That's why it's in the shop...I am having the transom replaced....I want it to be solid, especially with that big pig hanging off the back. I almost bought a lavey mod v 20.8 Sebring they are beautiful boats....I have always loved the lavey crafts.

I do have a bobs hydraulic jack plate and low water nose cone. There are so many more adjustments in comparison to a jet boat.....that's why I am nervous but also excited because it's all new to me. I guess I will have to buy a different prop if I wanna get higher speeds.....would be wise to have a spare anyways and keep the 26 bravo for towing ect... It sounds like you have these boats and their setup down to a science :) your advice and experience is very helpful.
 

BajaMike

Well-Known Member
Joined
Sep 20, 2007
Messages
6,322
Reaction score
3,073
Don't "prop for speed"....prop for RPMs. You should be able to easily get to the rated RPM red line with a full load of fuel, people, ice, and beer on a hot day.

Try to over prop "for speed" and you will have a busted crank (or worse) on an outboard in about 10 hours or less.

Good luck.
 

BigSteve

Well-Known Member
Joined
Dec 31, 2010
Messages
540
Reaction score
224
We just did a 20 Stoker project and were prop testing this weekend

With a 300 Yamaha 99.8 mph first time testing

I would get a hold of BBlades and ask to try a Yamaha TXP ( total excitement prop)

Its a 3 blade thru hub that will lift the boat nicely ( bow and tail )

The boats like to run with neutral trim / slight positive flat to the water

Driving a Stoker/ Baker is a little different from other outboards.
In how sensitive trim and jack plate height with the power setting.

Worn jack plate ,tilt bracket and worn engine mounts don't help sensitive boats.
 

Luv2gofast

Well-Known Member
Joined
Jul 1, 2011
Messages
329
Reaction score
266
Worn jack plate ,tilt bracket and worn engine mounts don't help sensitive boats.

X2 on that! hydraulic steering helps a lot also. It still takes effort to turn left but at least it's easy to hold once it's there. With cable you are fighting it all the time.
 

BigSteve

Well-Known Member
Joined
Dec 31, 2010
Messages
540
Reaction score
224
X2 on that! hydraulic steering helps a lot also. It still takes effort to turn left but at least it's easy to hold once it's there. With cable you are fighting it all the time.

Very good point !

We removed the old cable steering and replace it with hydraulic power steering! On the Stoker 20

Also I would replace the hydraulic jack plate and replace it with a R&R (slide master) plate
Two reasons the R&R Plate is much lighter and can be locked down solid (no movement)
I would pull the power head to verify the upper motor mounts are solid, not rubber.
And replace the tiller arm pivot bushing while down for inspection

I can't tell how important this is as a starting point :cool

Alan Stoker gave me this tip at the Parker race

He took 20' of rubber rope approx 3/8- 1/2 thick

He went to the rear of the boat, and used the rear tie down eyelets to loop the rubber rope under tension several times with the motor fully trimmed in and pulled it tight .
That helps control engine position even more.
When you trim to neutral it really tensions the rubber ropes.
Less vibration and when you trim it takes more pressure and you get better micro control in trim movements
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Thanks Baja Mike I will prop for rpms......definatley dont wanna bust a crank or damage the engine in any way....probably just cruise it the first season. After reasing these last posts I guess i will maybe be investing in hydraulic steering (i have dual cables) too FML it never ends.....again will take it slow this season.
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Ok so the 28 chopper works bitchen :) I am getting around 85-90 out of it! Not sure what my RPMs are cuz I am death gripping the wheel and pucker butt cheeks lol. Thanks for all the help. Love this boat but my wife hates it :-( she wants an open bow. uploadfromtaptalk1431110374207.jpg
 

Luv2gofast

Well-Known Member
Joined
Jul 1, 2011
Messages
329
Reaction score
266
Ok so the 28 chopper works bitchen :) I am getting around 85-90 out of it! Not sure what my RPMs are cuz I am death gripping the wheel and pucker butt cheeks lol. Thanks for all the help. Love this boat but my wife hates it :-( she wants an open bow.

Nice!! Yep I get that that pucker thing. Just starting to get comfortable enough to watch the tach on my Lavey. My son has an open bow Lavey...attracts too many friends.
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Yeah i think thats what she wants though. My friends are scared to go in it as it is. I think she just wants a cruiser that handles rough water better and can ski/tube behind. Outboards are badass but there are alot of factors and take alot more skill to drive opposed to jets. So unfortunately its up for sale :-(
 

ONE-A-DAY

Well-Known Member
Joined
May 21, 2010
Messages
18,098
Reaction score
25,629
I would contact KEVIN at the prop shop in Henderson, Nevada, he races your boat and owns a propeller shop, he would be the guy to get you dialed in while not trying numerous props to figure it out.

Mention my name, Walt Hollis #711
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Thank you, I will try and get ahold of him. I was just about ready to buy a spinelli 14.5 x 24 chopper. Still might depending on what he recommends. I am trying to get the boat to plain out with a boat load of people and porpoise less at slow speeds......right now it porpoises really bad unless I throttle through it......no matter how far I trim down.
 

Luv2gofast

Well-Known Member
Joined
Jul 1, 2011
Messages
329
Reaction score
266
Thank you, I will try and get ahold of him. I was just about ready to buy a spinelli 14.5 x 24 chopper. Still might depending on what he recommends. I am trying to get the boat to plain out with a boat load of people and porpoise less at slow speeds......right now it porpoises really bad unless I throttle through it......no matter how far I trim down.

I had a 28 Spinelli 4 blade that worked great on my Lavey. I broke a prop shaft and donated it to the bottom of Havasu. I don't think that will help your porpoising problem. It is probably balance. Too much weight in the back, which is what you want to go fast, but a problem at low speed. Is it worse with big friends in the back seat vs a big friend in the front seat and the back empty? The other possibility is that you have a rocker (opposite of a hook). Easy to check by laying a straight edge along the last 24" of the center pod. Actually the last 6 to 12" is most critical but since it's a low speed problem you should probably check the full 24. Also too much set back but it doesn't look like you have much from the picture. A 4 blade might help and you may want to try a Bravo also. A through hub might hook up more solid at low speed.
 

Wolly42608

Well-Known Member
Joined
Jan 10, 2014
Messages
52
Reaction score
0
Thanks,
I will take a look at the bottom and see if i notice a rocker or hook. Yes it does seem to be worse with friends sitting in the back apposed to middle or front. I might try a low pitch thru hub prop to see if that helps....like what you suggested with the bravo. I am after a prop that i can use for cruising and possibly skiing (if its flat enough) and that can carry a load better so i have more low range when it gets choppy i dont wanna hammer the boat and passengers.
 
Top