Should my motor be faster? see video *updated w/ prop pics *

[minicuda]

I have a 25 horse nissan on a 1648 i think it should be faster. I have no idea about the prop on it. i feel like it should be running at higher rpm at full throtle. i need to get a tach and see where its at. what can i do to make it faster? please watch the short video and tell me what you think. when my son pans the camera out the back i'm wide open full throtle.

https://s154.photobucket.com/albums/s273/minicuda/?action=view&current=boat034.flv

 

[bassboy1]

Can't tell you anything till you have a tach. Check out Tiny Tach (google it).

Do you have a speed measurement? Next time out, run up one section of lake at WOT, timing it, then take a chart, and measure the distance. You should be able to calculate a rough speed estimate from that.

 

[whj812]

Looks like its running at a pretty good speed for a 25!

 

[papasage]

see if you can find some one that has a GPS . a lot of fishermen have them to mark good spots . some have them in the fishfinder . 55 hp on a bumblee bee runs 29 MPH . i have a 75 hp on a cimaron bass boat both 15 ft . the 75 runs about30 . both checked with a GPS.
my pontoon witha 40 hp runs 15 mph .

 

[minicuda]

how fast do you guys think a 25 horse 2 stroke on a 1648 flat bottom jon should go? i'm going to get ahold of a gps and a tach and see what she does

 

[bAcKpAiN]

Might be a trim/height issue. It looks like you are throwing alot of spray straight up from the motor to me.

 

[minicuda]

Might be a trim/height issue. It looks like you are throwing alot of spray straight up from the motor to me.

i thought it was spraying alot to. what should i do? raise lower or tilt?

 

[seaarc]

I agree get your hands on a gps and check it that way. If I get a 25hp for mine and it runs that fast I will be very pleased cause it looks like your moving along at a pretty good clip. Be sure to post your results.

Dave

 

[bAcKpAiN]

Might be a trim/height issue. It looks like you are throwing alot of spray straight up from the motor to me.

i thought it was spraying alot to. what should i do? raise lower or tilt?

I dunno, I would wait for someone more experienced to give some advice. I am not sure which way honestly.

 

[Zum]

Some people say they can tell the rpm by the sound the outboard is making.I can't but yours did sound pretty good to me,planed out,wasn't slapping.There was some water coming straight up,not sure what that means,mine does that to,can fix it by tilting out but then it will slap a bit.
My boats similar to yours and it's rated for a 60hp with a console,yours being all decked out probably going get around 20mph(just a guess).I have a 30hp tiller going GPS it in the next day or so,I'll let ya know what I get.

 

[sccamper]

Looks good to me, wish mine went that good. Ive got a 1436 flat bottom; front deck, wood floors, 2 tm, ect. '72 20hp. Runs 18 mph with me and gear. With 2 people and gear, sometimes it wont plain out.

 

[minicuda]

look at this video for comparison its a heavier boat at 400 pounds mine is 200. he has 2 larger guys in it 835 total weight and he is clipping along at almost 30. however he is in a v bottom not sure what differance this would make. I can't help feeling i could get more out of her.

https://www.youtube.com/watch?v=Tsl0S6KaR6k

 

[Zum]

Don't see the video...but your 16 foot boat only weighs 200 lbs?
Especially with all the decking

 

[minicuda]

Don't see the video...but your 16 foot boat only weighs 200 lbs?
Especially with all the decking

no without the decking just the hull.... added the video :wink:

 

[Zum]

Not sure if a V goes through the water better than a Jon boat.
I can tell you today I borrowed a friends GPS and my 1652 went 27.5mph with a 30hp at 5700rpm,11 pitch prop.Just by moving the battery in the bow I lost 1.5mph,didn't seem like it but thats what the GPS said.
Maybe try moving what you can around and see how it affects your preformance+,-.

 

[BassNBob]

I have a 2000 25 Nissan electric start, tiller handle, on a 14 foot Nova ultra jon and yesterday on the lake it was running 24mph with me only. My motor is set up on the fourth hole from the transom. I just recently installed a 70 inch 3/4" deck on the front and covered the rear bench with 3/4" plywood which added more weight. If you go to the Nissan Outboard Forum they have Q&A for these issues also and hoh to convert your 25 to a 30 HP. Just a suggestion. I'm satisified with my speed for now, I just wish I had a steering wheel. Good luck.

 

[BassNBob]

I went outside to check the motor location on the transom and it is in the third hole up from the transom. I was using a GPS unit for my speed. I don't have a tach.

 

[Jim]

Was doing some research to try to help, and I ran across this. Read through the thread, One guy gives a few possible reasons that might be true with yours?

I also noticed the first video shot of therear of the boat it was only spraying on the right hand side...then it sprayed on both sides :-k


https://www.boatdesign.net/forums/showthread.php?t=22938

 

[Zum]

Nice Link.
Good idea for the TM lock..BnB

 

[minicuda]

thanks for all the help everyone you guys rock!