A couple of speed questions from a total pontoon newb

[Krochus]

First off a little of my boating background to help y'all understand where I'm at in all things pontoon. I've had experience with tri hulls, bass boats and various John boats. I now own a new v20fc sun catcher with a 70hp Yamaha four stroke.

My question falls into two parts both speed related.

FIRST when underway from no wake speed to wot my toon seems absolutely unresponsive to trim adjustments. She runs out best and fastest trim down all the way. This is counter to my previous experience, is this fairly normal for a pontoon?


SECOND based purely on my limited research my boats at best 20mph speed seems slow. Especially since 4500rpm at 2/3rds or so gets me 15. I'm thinking a prop change is called for as 5000 rpm is about all I can wring out of the motor.

Thanks in advance for the input.

[bobalong]

I have only been running a pontoon for a couple of years, but your speed, sounds about right, maybe a tad slow, I get about 20mph on my 60hp at wot. Trim does little to nothing on mine as well

[ROLAND]

First off a little of my boating background to help y'all understand where I'm at in all things pontoon. I've had experience with tri hulls, bass boats and various John boats. I now own a new v20fc sun catcher with a 70hp Yamaha four stroke.

My question falls into two parts both speed related.

FIRST when underway from no wake speed to wot my toon seems absolutely unresponsive to trim adjustments. She runs out best and fastest trim down all the way. This is counter to my previous experience, is this fairly normal for a pontoon?


SECOND based purely on my limited research my boats at best 20mph speed seems slow. Especially since 4500rpm at 2/3rds or so gets me 15. I'm thinking a prop change is called for as 5000 rpm is about all I can wring out of the motor.

Thanks in advance for the input.

As far as noticing a difference when adjusting the trim level, I can tell a small difference on my boat... not a great great difference but some... as for speed, I too have a 20 footer that has a yamaha 75 on the back... top end when it was new was approx 23 mph...

[wwind3]

If you have a lot of weight on the front end---couches, etc---trim may not help much. Underskinning will help a little to create front end left. And will keep waves from hitting crossmembers which will slow you down.

Next-check what your max operating speed on the motor is and get a prop that will operate at that speed wide open.

Are you running max engine HP for that boat? Makes a difference. Finally---size of pontoons? Larger will help with buoyancy even tho they are probably heavier.

btw trimming my motor makes a huge diff--for instanc---at cruise---around 18mph and 3800 rpm. Hitting just the trim-no throttle input---rpm's increase to around 41-4200 and speed goes to 20-21 gps. All due to front end lift.

I am getting 29 with my setup---see my sig line. Good luck....

[cleatus]

yeah, trimming a toon is way different than a v hull, try to find the sweet spot and fugetaboutit, I adjust trim when I have people seated near the bow, otherwise it doesn't effect the ride that much.

your speed is a bit slow, you should be getting 5500-5700 rpm, check your prop pitch, i'm running a 13P on a yamaha 70F on a 20 footer with 27" logs and get 25mph with 2 adults and a big dog on board.

weight really makes a difference, the new concept yammy 70F only weighs 260 lbs.

[Krochus]

Thanks for the feedback guys, you're confirming what I was suspecting but had no firsthand experience with.

My toon being a fish cruise hybrid is probably a bit stern heavy. By trim not doing anything from down to part up its unresponsive on the speedo or tach up to the point the bow starts to pitch up and the speed slows even more.

The hull is rated for 90hp maximum

To the positive fuel economy has been outstanding!

[Bamaman]

Twin toon boats without lifting strakes are displacement hulls, meaning they plow through the water. On my old Starcraft 24' w/115 hp 2 stroke, I found the power trim to do little to improve speeds. My Starcraft will accelerate like a bass boat to a certain speed, and then it's like hitting a wall. It just won't go any faster.

When you get 115 hp and lifting strakes, the power trim is very good to lift the nosecones out of the water. That's when pontoons get up and run.

You should consider dropping down a couple of inches of pitch--to get your engine up to 6000 rpm's. Otherwise, that's about all you can do as you're limited to how fast the boat goes plowing through the water and by horsepower limitations.

[brumbyvet]

Yea, I agree. Change props to get your rpm's up but without strakes your not going to get much trim.