Unstable 5.1 m ali

My 5.1 m allly craft is very unstable on the water. I suspect that the Honda 75 HP 4 stroke is too heavy for the vessel !!!

Maybe downsize to smaller motor, even to 50 HP two stroke !! Moving from side to side is a big issue. !!

Any suggestions

Posts: 713

Date Joined: 22/07/10

 Unstable at rest or on the

Thu, 2020-04-09 13:27

 Unstable at rest or on the plane.

Posts: 3

Date Joined: 29/11/19


Thu, 2020-04-09 13:30

Hi squidvicious1,

Unstable at rest, can't have two people on one side, otherwise in danger of falling over side !!

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Date Joined: 06/05/12

 Is there a canopy?  It can

Thu, 2020-04-09 13:37

 Is there a canopy?  It can change the centre of gravity.

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Date Joined: 29/11/19

No canapy 

Thu, 2020-04-09 14:21

No canapy


quadfisher's picture

Posts: 1094

Date Joined: 28/09/10

Stay low and pray!

Thu, 2020-04-09 13:47

 Yeah first question as above , at rest? 

 I have a 4.95m haines profish with the good old 20 degree deadrise., and at speed its fine and seems stable on waves etc

 At rest however you are never going to get it to sit flat like a 15 or 16 degree hull. ( but mine rides like a 5.8 boat)

 But with now 18 months of use I have become used to its feel and although its first few degrees of list happen quite quickly it then settles 

 and seems safe to me , and Im not talking about in the river , had it miles out to sea in some less than perfect days and never had a drama.

 My fishing buddy and me have become used to physical distancing to each other long before it came a thing.

 And I would have to believe haines wouldnt release a boat to market thats inherently unstable and thus I have proved it to myself.

 I have a 4 stroke 70 on it but its rated to a 90, by my reasoning a slighty larger motor on the keel line should help sideways stabilty.

 If yours unstable underway I dont have any tips , but in mine i keep the 90 l belly  tank mainly full and store all heavier items along the keel line.



Posts: 585

Date Joined: 22/08/12

Put a boat collar on it

Thu, 2020-04-09 13:53

 they are made in Queensland from memory. You can do it yourself. Search  Kapten boat collar and see them in action. Prob cost aroud 2 grand. Just a thought cheers dave

Posts: 585

Date Joined: 22/08/12

Sorry forgot to add you can also add transom floatation to the

Thu, 2020-04-09 13:55

 back to counter the heavy motor and fisho's standing in the back at rest 

carnarvonite's picture

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Date Joined: 24/07/07


Thu, 2020-04-09 13:57

 Add a few photos  showing the shape of the stern plus another showing if you have a canopy or rocket launcher as both of these can greatly affect stability

scubafish's picture

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Date Joined: 15/08/12


Thu, 2020-04-09 15:47




Striker101's picture

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Date Joined: 20/03/20

 Try a fibreglass 5.1 metre

Thu, 2020-04-09 16:51

 Try a fibreglass 5.1 metre ;)



Tim's picture

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Date Joined: 26/09/06


Thu, 2020-04-09 18:14


Really need photos of it on the water

I dont reckon the 75 is too heavy. Should be about right. 

Sometimes it can be its not heavy enough and is not sitting on the chines at rest

Posts: 253

Date Joined: 08/06/15

May sound like a silly

Thu, 2020-04-09 21:21

May sound like a silly question, but have you checked to make sure there is no water sloshing around in the hull. Mate of mine had the same issue a few years back. Turned out he had some water in there changing the centre if gravity.