Pontoon Boat & Deck Boat Forum

Hi,

I have a 2008 starcraft limited 206 RE CR with a 90 hp mercury 4 stroke on it. I've had numerous people tell me it should be going a lot faster than 23 mph, and that's with only 2 adults in it.

I've had the dealer take it out and all they said they can do is verify that the engine is running at the right RPM's (5900) which it is. They looked up the prop pitch with mercury, and they said that is fine too.

Other than that, they just give me the generic "we can't really guarantee any kind of speed". I understand that, but 23 mph is so low.

I'm starting to wonder if it's the design of starcraft pontoons that are causing the performance problem. I guess I'm just looking for some advice.

Thanks,
Brian

Starcraft is and always has been a high quality boat and has been in business over 100 years. Never heard any design problems from them at all. Others can comment who have similar setups/hp, but you may want to experiment a bit with different props. Have you tried playing with the trim while underway (raising the bow) ?

If it is slow, it's not by much. Consider the amount of weight, number of people, coolers, etc.

A 20' Pontoon with a 90 4S getting 23 MPH is a tad slow.
Seems that's a common number for 22" with a 90 4S and that's what I get.
You should be getting a few MPH more, say around 26 - 27.
Your WOT RPM seems right, but you could try a different prop.

Thanks for the replies.

I've played around with trim settings. So did the dealer. They put a pin in to keep me from trimming it down too much, which really slows it down.

I could try different props, but didn't think it was worth the time and money for a couple MPH. I have a friend who was on the boat the other day and he said he ski's behind his dad's pontoon with only a 75 on it, but I doubt mine could pull someone out of the water.

jordabr wrote:Thanks for the replies.

I've played around with trim settings. So did the dealer. They put a pin in to keep me from trimming it down too much, which really slows it down.

I could try different props, but didn't think it was worth the time and money for a couple MPH. I have a friend who was on the boat the other day and he said he ski's behind his dad's pontoon with only a 75 on it, but I doubt mine could pull someone out of the water.

I can pull up ski'ers and wake boarders easily with my 115... You might have a prop designed for quicker acceleration rather than top speed (which makes more sense in a pontoon anyway in my opinion)! Find a dealer who will let you try out several sizes and pitches until you find the one you like best!

My 22 ft Bentley with a 90hp Merc Optimax 2 stroke with 2 adults will get 22 mph GPS on smooth water.

Does your boat have lifting strakes and is it underskinned? Those are the two upgrades I am considering to squeeze that 2 to 4 MPH extra out of it, but in reality for a 2 toon pontoon that is about where I think I should be.

I have a 20 footer with a 90 2 stroke and the best I have ever got with a gps is 24.

We have a 20' with a 90 and you might get a nother 2 mph out of her depending on your weight. 5900 rpm is where I tach out at and we can get about 24 mph with two adults and a 30 pack. Check the bottom of your tubes to make sure they are clean. I can lose two mph with dirty tubes.

NEBSTER wrote:We have a 20' with a 90 and you might get a nother 2 mph out of her depending on your weight. 5900 rpm is where I tach out at and we can get about 24 mph with two adults and a 30 pack. Check the bottom of your tubes to make sure they are clean. I can lose two mph with dirty tubes.

Read my sig for my setup--I hit 30 gps early this spring by myself---now in the summer I get 28 by myself, 26 with me and the wife.


Will be 100 degrees tomorrow- I may run it and see if the air density affect the speed---even tho I am fuel injected---it seems to run faster in cooler weather.

What is underskinning, and does that affect speed?

here is a great example of skinning

yes it helps with speed it cuts down drag under the toon I am hoping to taking this project up this fall my big pig needs all the help she can get...

http://pontoonforums.com/viewtopic.php? ... ing#p15283

What is your pontoon diameter?

wwind3's are 25" diameter tubes, I bet yours are 23" diameter which was standard with Starcraft for a long time.

So more of you tubes are underwater, your engine has to push more water out of the way, and you go slower than a different 20 foot toon with wider pontoons.

Your numbers are not unusual.

I have a 2006 - 20' with a NEW Merc 90 4 stroke. I have had it out twice this year and at WOT 6200 RPM I can hardly get out of my own way. Proping is correct cause I have played with different pitches. I have trimmed up and down and all around. I even pressure tested my tubes. Im also being told the front of the boat sits low like its taking a nose dive. No over weight people or tons of baggage on board. I keep thinking poor design on the tubes??? Can anyone help??

thanks
Jaimie

A good speed for that combination I would guess is around 24-27 mph. If your starcraft looks like the ones I found for that model, you may be a little front heavy. With all that furniture and maybe a couple of mates up front, your front end is plowing on a 20 footer. Even the driver is sitting up front on that toon.
On my 20 ft/50hp toon, I can have 2 people up front going 16-17 mph, move them to the back and increase to 18-19mph. In the best conditions I can get 21 mph. My boat doesn't have much furniture up front.
Post some pictures


On another note. Cold water is denser adding lift to the logs and bite to the prop. And cold air is also denser making is easier to get more into the engine.