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 Porpoising bad (update fixed) 
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Post Porpoising bad (update fixed)
Ran rig today. Me and the two kids. As soon as I started to trim up, bouncing bad. They had to actually sit on the 15 gal gas tank (which was full) to get it to stop. With 15 gal of fuel and about 200+ lbs on the front deck, ran 30 mph at 4500 all day. As soon as they tried to get off deck, bitch started bouncing. I tried to run by myself, and with the prop completely buried, ran 28 at 4250. As soon as I tried to trim any, I immediately felt it speed up, real quick but bouncing like it was gonna knock the front end off.

The boat has a double taper transom. I saw on an older thread where wedges were made to help out. I'd rather make wedges that weld some bead on there. Anyone running these wedges.

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Sat Jul 20, 2013 3:24 pm
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Post Re: Porpoising bad
Sounds like you need a boat!

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Sat Jul 20, 2013 3:43 pm
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Post Re: Porpoising bad
Try dropping pin a notch. Report results. I'm presuming you have pin in middle hole.

If that solves your bouncing, install shim and put pin back in middle hole.

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Sat Jul 20, 2013 4:08 pm
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Post Re: Porpoising bad
dguidry wrote:
Try dropping pin a notch. Report results. I'm presuming you have pin in middle hole.

If that solves your bouncing, install shim and put pin back in middle hole.


Come again. I have a PD

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Sat Jul 20, 2013 4:16 pm
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Post Re: Porpoising bad
banded-mallard wrote:
dguidry wrote:
Try dropping pin a notch. Report results. I'm presuming you have pin in middle hole.

If that solves your bouncing, install shim and put pin back in middle hole.


Come again. I have a PD

Never mind then.

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Formerly:1648 Homemade Cypress Crawfish Skiff GTR23 Performance Cam and Heads. Currently: 17x46 Gator Tail with 35GTR and Hoyt's cam.
“Wisdom is not just expertise. It is knowing how much of various areas of expertise you need to know in order to make the decisions that the world needs and that you want to do,” Columbia University President Lee Bollinger.

Please enter your boat data here: https://spreadsheets.google.com/viewform?hl=en&hl=en&authkey=CJCrk_oF&userstoinvite=ellidupre%40gmail.com&formkey=dHJVb0tOMWFUV1hZWDFTNFhZalZOUVE6MQ#gid=0

View all boat data here:https://spreadsheets.google.com/pub?hl=en&hl=en&key=0Al4r1k-hlfeIdHJVb0tOMWFUV1hZWDFTNFhZalZOUVE&output=html


Sat Jul 20, 2013 4:20 pm
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Post Re: Porpoising bad
banded-mallard wrote:
dguidry wrote:
Try dropping pin a notch. Report results. I'm presuming you have pin in middle hole.

If that solves your bouncing, install shim and put pin back in middle hole.


Come again. I have a PD


Search for Deans handy dandy trimmy tabbies. That may help :lol:


Sat Jul 20, 2013 4:26 pm
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Post Re: Porpoising bad
^^ :lol: :lol:

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Sat Jul 20, 2013 6:35 pm
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Post Re: Porpoising bad
That's gotta suck! :lol:

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Sat Jul 20, 2013 6:59 pm
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Post Re: Porpoising bad
Good news is it's an easy fix....bad news is it will cost you a touch of top end. Wedges, small hooks, or weld beads will fix it.


Sat Jul 20, 2013 7:25 pm
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Post Re: Porpoising bad
Yeah. Gonna try the small wedges similar to some others I've seen.

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Sat Jul 20, 2013 8:04 pm
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Post Re: Porpoising bad
What size boat is it?

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I've never gone to Seminole for the amenities/luxury the two reasons I go down there are to kill shit and get fucked up with like minded individuals aka OG'S. If you want to swirl wine and stay in a room where politics and investment diversity are discussed (with no roaches) lake lanier is near Atlanta. If you wanna have an awesome time and maybe stay in a room where children were conceived on one side and someone got stabbed over an 8-ball on the other come on down I got a can of raid. :D


Sun Jul 21, 2013 4:56 am
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Post Re: Porpoising bad
17'10"x48

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Sun Jul 21, 2013 6:40 am
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Post Re: Porpoising bad
banded-mallard wrote:
17'10"x48

A boat that long and gas tank up front shouldn't be doing that.

Whats your transom angle?

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Sun Jul 21, 2013 6:54 am
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Post Re: Porpoising bad
Double taper transom ! Would that be kinna like a 2 step pad on a high performance glass boat! ?or is the taper on the transom itself ?


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Sun Jul 21, 2013 6:57 am
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Post Re: Porpoising bad
lazarus wrote:
Double taper transom ! Would that be kinna like a 2 step pad on a high performance glass boat! ?or is the taper on the transom itself ?


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Missed that Double Taper. That always fucks up boats. There is no need for a tapered transom.

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Sun Jul 21, 2013 7:18 am
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Post Re: Porpoising bad
Did it because of where we hunt. Gets real bad. My old boat didn't have it and buddy's did. He had no prob backing out of spots. I did, so I decided to do it on this one.

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Sun Jul 21, 2013 8:41 am
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Post Re: Porpoising bad
banded-mallard wrote:
Did it because of where we hunt. Gets real bad. My old boat didn't have it and buddy's did. He had no prob backing out of spots. I did, so I decided to do it on this one.

It seems that all the tapered hulls I have seen squat bas in the back and bounce up front. They all have to load all their ice chest and weight up there.

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Sun Jul 21, 2013 9:06 am
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Post Re: Porpoising bad
I'm headed to NO to leave for a cruise. I'm gonna try some small tapered wedges when I get back. If after all that I still can't get it straight I can always box it back in. Need to do something. I know by myself if I can get it to flatten out, this bitch is gonna roll. Gonna do something like this with the long tapered wedge rather that a weld bead.

http://www.mudmotortalk.com/mmt_v2/viewtopic.php?f=3&t=39431&p=482739&hilit=Porpoising#p482739

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Sun Jul 21, 2013 9:23 am
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Post Re: Porpoising bad
Welded beads are so simple man. I would try that first. If it dont work you can always grind them off.

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Sun Jul 21, 2013 9:32 am
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Post Re: Porpoising bad
Actually be talking to Preston last night. Gonna use a 2 part putty. Roll it into a 3/8" snake. Stick it to the bottom and taper it. Dries pretty fast. Go run it. If its too much, can manipulate it to get it right. When right, then make some permanent

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Sun Jul 21, 2013 9:53 am
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Post Re: Porpoising bad
Hell yea! Go have fun and fuget for now.

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Sun Jul 21, 2013 10:08 am
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Post Re: Porpoising bad
Yep. I normally come up with some of my best ideas drunk. And then there are some of the stupidest.

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Sun Jul 21, 2013 10:35 am
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Post Re: Porpoising bad
I had a 36 PD on a 16-44 go devil and it ran like a scalded dog. Never had issues with porpoising

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HOTSAUCE170 wrote:
I've never gone to Seminole for the amenities/luxury the two reasons I go down there are to kill shit and get fucked up with like minded individuals aka OG'S. If you want to swirl wine and stay in a room where politics and investment diversity are discussed (with no roaches) lake lanier is near Atlanta. If you wanna have an awesome time and maybe stay in a room where children were conceived on one side and someone got stabbed over an 8-ball on the other come on down I got a can of raid. :D


Sun Jul 21, 2013 10:39 am
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Post Re: Porpoising bad
banded-mallard wrote:
Actually be talking to Preston last night. Gonna use a 2 part putty. Roll it into a 3/8" snake. Stick it to the bottom and taper it. Dries pretty fast. Go run it. If its too much, can manipulate it to get it right. When right, then make some permanent

Thats exactly what preston done on my boat. It worked like a charm


Sun Jul 21, 2013 11:50 am
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Post Re: Porpoising bad
Yeah try niggering it and if that don't work get a new fuking boat!Damn

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Sun Jul 21, 2013 1:06 pm
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Post Re: Porpoising bad
JIMMY W wrote:
Yeah try niggering it and if that don't work get a new fuking boat!Damn

It is new. Don't worry, I don't ever rig shit. If I'm gonna do it, I don't care how long it takes, it will be done right. Even if I have to box in the tapered transom

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Sun Jul 21, 2013 1:55 pm
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Post Re: Porpoising bad
I would fill in the back i have 1656 godevil it was bad its a different boat now. i hated running that boat by myself


Mon Jul 22, 2013 6:53 pm
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Post Re: Porpoising bad
banded-mallard wrote:
Actually be talking to Preston last night. Gonna use a 2 part putty. Roll it into a 3/8" snake. Stick it to the bottom and taper it. Dries pretty fast. Go run it. If its too much, can manipulate it to get it right. When right, then make some permanent



viewtopic.php?f=3&t=39431


Mon Jul 22, 2013 7:34 pm
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Post Re: Porpoising bad
Those tapered wedges are exactly what I gonna do. If that doesn't work, I'll just box off the back in and take the taper out.

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Sat Jul 27, 2013 10:32 am
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Post Re: Porpoising bad (update fixed)
Played with various wedges today and found a sweet spot between to much down force and running right on the edge of bouncing. From there I can move some weight around and make it better.

Ran consistent 30 all morning bumped 31 twice. That's a 3-4 mph improvement from before. Now I have to get motor tuned right.

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Sun Jul 28, 2013 1:12 pm
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Post Re: Porpoising bad (update fixed)
I'm having a similar problem. When my boat is loaded down, which TBH is most of the time, I dont have too much of a problem. When I'm by myself on the other hand, it porpoises out of control. I was wondering if you could elaborate a bit on these wedges you made... You mentioned 2 part epoxy? Did you use that and change the aggressiveness of the angle until it rode right, then get some aluminum ones made? Got any photos?


Tue Oct 03, 2017 8:47 am
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Post Re: Porpoising bad (update fixed)
This thread is 4 years old. You skimmed pass the link that has the pics, it was posted. I no longer use those wedges, slowed boat down too much.

http://www.mudmotortalk.com/mmt_v2/viewtopic.php?f=3&t=39431&p=482739&hilit=Porpoising#p482739

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Mon Dec 11, 2017 5:51 am
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