Porpoise

[Chopperbill]

Back out to AZ for the winter. Lost lot of weight over the year, now have to reconfigure boat. Solo I can run 1/2 to 3/4 throttle pretty good but when I open it up or porpoises big time. I put every thing I had in the boat up front and the fuel tank as far as the fuel line allows. I have a one foot tiller extension and ride in the middle of the boat and it calms down pretty good but a wake from another boat will get it porpoising again. Wife goes with me and rides in the bow and it performs well. What you guys use for ballast to put up front when riding solo? Neighbor suggest a couple of cinder blocks but I dot think I want to use those. Motor is in first pin hole and has a very good wake so I don't think I have a problem in set up.

 

[ronaldj]

You may want to try putting a cooler up front
I have a friend with the same setup you have.
I will reach out to him to find out what he does.
He checks this forum occasionally so he might get back to you before I do

Btw
Your outboard is short shaft right ?

 

[Chopperbill]

Short shaft. Just came back with wife in bow. Still wants to porpoise, but not as bad. Aired to max. Seem like every weight change it has to be delt with. Are RIBs this much problem? I just want to rip the throttle and go. This is getting to be a real pain in the butt!

 

[211libwtfo]

Have you tried moving the pin. Or try shimming the transom clamps that mite be a Lil billhillie but whatever works.

 

[ronaldj]

Short shaft. Just came back with wife in bow. Still wants to porpoise, but not as bad. Aired to max. Seem like every weight change it has to be delt with. Are RIBs this much problem? I just want to rip the throttle and go. This is getting to be a real pain in the butt!

Send Sinistre1 a PM
He has the same setup that you do.
In fact you have talked to him before.

 

[Scott Danforth]

You have to adjust the tilt based in load. On my little tinny i adjust 2 pin holes if my buddy comes with me. There is no one-setting and forget it

 

[Chopperbill]

Pin is in the first hole next to the transom. Pin positioned any further back will make it worse. It's like I need one more hole.

 

[Scott Danforth]

or in this case, transom wedges to angle the motor a bit more to get you adjustment.

http://www.iboats.com/Boat-Parts-Ac...hed.1--filter.prod_name?q=transom wedge&s=sol

 

[Sea Rider]

If remenber right your Sib is an inflatable deck , right ? If so, will need to air top tubes, air deck and keel as well with gauge. In reality if OB is 101% healthy, sits at the sweet transom height, that's water flow passing at speed right under upper water deflector plate, deck weight is evenly distributed and trim is set at a hole for anticav plate to run parallel to water level once on plane don't need to play with trim again.

Should remain at that "fixed hole position" if adding more passengers, it's just a matter of knowing your inflatable water behaviour and distributing weight evenly on deck The isssue is that nobody pays attention to perfect OB height, which is the first thing you should check during initial first wot trials. Most times it's not a matter of sitting OB on transom and voil? if wantig super water performance and fun.

Happy Boating

 

[Chopperbill]

Will transom wedges work on a clamp on motor ?

 

[fhhuber]

Will transom wedges work on a clamp on motor ?

If you can keep the wedges from moving... and if they don't effectively make the transom too thick.

I would consider gluing and or bolting the wedges in place once you have determined how much wedge to use.

The wedges for clamp on would just be solid wood. Like oversize door shims.

 

[Chopperbill]

Just took a look. Plenty of room for a wedge. I'll see what I can find.

 

[Chopperbill]

What a dumb @$$!!! Took boat for a ride solo again after putting in a shim. Same porpoise deal. The back of the floor was doing the rolling thing. Coming back I noticed a lump in the back third of the floor. Brought it back to shore and let the air out of the floor. The back three feet of the keel was folded up towards the front!
Got it aired up and it looks good. No doubt it's going to work a lot better.

 

[ronaldj]

What a dumb @$$!!! Took boat for a ride solo again after putting in a shim. Same porpoise deal. The back of the floor was doing the rolling thing. Coming back I noticed a lump in the back third of the floor. Brought it back to shore and let the air out of the floor. The back three feet of the keel was folded up towards the front!
Got it aired up and it looks good. No doubt it's going to work a lot better.

Don't be so hard on yourself
It could have happen to anybody

 

[Chopperbill]

No Title

Got back out. Runs much better! LOL Still a some roll at certain speeds. Took my Saturn seat frame, that I wasnt using and covered it an installed. The front section of the boat comes with a 1/2 x 12 board under the floor to make solid. The aluminum tubes eliminated any roll! Planes easy and rides better. Even going over a wake or wave is more comfortable. The floor is probably as solid as a aluminum or wood floor.

 

[Sinistre1]

Chopper... did you ever get to use that as its intended use floor seat frame... was it stable and or did you ever feel like it would pop out under way? Mostly been watching the threads these days... especially yours since we have the same exact set up as RonaldJ has mentioned. Haven't gotten time to play with mine much but im thinking about a seat using that frame

 

[Chopperbill]

No way it will pop out. Well, there are guys that can break an anvil with a rubber mallet. LOL. My big problem is the seat mounts were mounted too much to one side and when I tried swivel the back would hit the tube. I modified the seat and made it better. I just found sitting on the floor was about the ideal place on an inflatable because you can shift your weight around for the load and more comfortable because you can move around easier. The new seat frames are smaller diameter tubes and cheaper if you want to try one.

 

[Sinistre1]

Thanks!!! I'm definitely going to give that a try this season, I need to update my profile. It should read like yours. lol

 

[Chopperbill]

Thanks!!! I'm definitely going to give that a try this season, I need to update my profile. It should read like yours. lol

Yeah that EFI Suzuki is a great way to go. One pull starting when cold and idles right off. Sips fuel.

 

[ronaldj]

Chopper
I have the same seat frame
I also have the console that goes with it.
My initial problem with the seat frame was that I couldn't find any pedestals that were good at high speed.
5mph seems to be the norm on speed.
I want pedestals more substantial.
Anyway I did much the same thing you did.
I covered my seat frame and moved it up front to be used as my crabbing platform
I like the way yours is carpeted however and I will have to do that to mine.
Thanks for the tip