Reply
 
Thread Tools Search this Thread
 
Old 28 April 2014, 12:15   #11
Member
 
Country: UK - England
Town: Oop North
Length: 3m +
Join Date: Jul 2013
Posts: 323
I'm sure all Sibs can take bigger engines than the maximum stated on the Transom. But the maximum stated is there so the SIB can operate within its safe limits. Exceeding the maximum stated engine size could push the SIB beyond safe operation.

If you decide to use a bigger than stated outboard, then I'd recommend trying to get specialist insurance cover, because a claim on normal cover would be thrown out because you breached it's terms and conditions.
__________________

__________________
stray is offline   Reply With Quote
Old 28 April 2014, 14:33   #12
Member
 
Roflhat's Avatar
 
Country: UK - Scotland
Town: Isle of Lewis
Make: Ceasar Thundercat
Length: 4m +
Engine: Yamaha 70ces
Join Date: Jul 2010
Posts: 633
RIBase
Just use a 25hp and remove the restrictor, will give you 30hp (depending on what kind of engine of course).
If it were me I'd slap a 50hp on the back.

If possible you may want to strengthen your transom to take the extra power as well
__________________

__________________
Roflhat is offline   Reply With Quote
Old 28 April 2014, 15:58   #13
Member
 
Country: UK - England
Town: Plymouth
Make: Avon
Length: under 3m
Engine: Cresent 14hp
Join Date: Mar 2012
Posts: 3
Thank you for your replies, as a novice to boating ( been out couple times with my mates) I presumed that all 30hp engines are the 25hp engine just without them being restricted. The engine I have is a 2 stroke 2 cylinder ( 2 spark plugs ( sticker says one is16hp and other is 14hp) ). I also I understood that the transom can often hold more weight etc however they lower it as a way to cover their self from liability if a transom was to fail. My example of this is my boat is roughly 3-4 metres which states it holds a 40ph (2 stroke back then) however the newer boats which are the same size are rated to a max of 30hp( ie the hon waves ) however most of the avon sports only go up to 25hp. So being the same boat pretty my question is surely it wouldn't effect the boat at all as it's only 5 hp more then it states? I realise in terms insurance it might be an issue however I would have asked that once someone gave me there experienced knowledge about the issues it might cause. I'm sure plenty of people have put a bigger engine on a boat then stated. I obviously I wouldn't put a 50hp on a transom maxed at 25hp but surely a 30hp on a 25 wouldn't be that bad?
__________________
Stevenmb is offline   Reply With Quote
Old 28 April 2014, 15:58   #14
Member
 
Country: UK - Scotland
Make: Destroyer 5.5/Ring18
Length: 3m +
Engine: Yam 90HP/Yam200HP
Join Date: Jul 2009
Posts: 447
Quote:
Originally Posted by steco1958 View Post
If you put a larger engine on the rear of a rib, or sib that it is rated for, you instantly give any insurance the excuse they require not to pay out if anything goes wrong.

If that was the case, and it was me you injured, I would come after you with a very big solicitor and take everything you owned, possibly even your freedom. limits and rating are there for a reason !!

If your insurance company insure a bigger engine, what's the problem?
__________________
69cmw is offline   Reply With Quote
Old 28 April 2014, 16:02   #15
Member
 
henryfreston's Avatar
 
Country: UK - England
Town: Thornbury
Make: Avon Searider 4m
Length: 4m +
Engine: 50hp tohatsu tldi
Join Date: Sep 2012
Posts: 648
Quote:
Originally Posted by Stevenmb View Post
Thank you for your replies, as a novice to boating ( been out couple times with my mates) I presumed that all 30hp engines are the 25hp engine just without them being restricted. The engine I have is a 2 stroke 2 cylinder ( 2 spark plugs ( sticker says one is16hp and other is 14hp) ). I also I understood that the transom can often hold more weight etc however they lower it as a way to cover their self from liability if a transom was to fail. My example of this is my boat is roughly 3-4 metres which states it holds a 40ph (2 stroke back then) however the newer boats which are the same size are rated to a max of 30hp( ie the hon waves ) however most of the avon sports only go up to 25hp. So being the same boat pretty my question is surely it wouldn't effect the boat at all as it's only 5 hp more then it states? I realise in terms insurance it might be an issue however I would have asked that once someone gave me there experienced knowledge about the issues it might cause. I'm sure plenty of people have put a bigger engine on a boat then stated. I obviously I wouldn't put a 50hp on a transom maxed at 25hp but surely a 30hp on a 25 wouldn't be that bad?
There is no performance problems using a 30hp, its just if the insurance company will play ball.
__________________
henryfreston is offline   Reply With Quote
Old 28 April 2014, 17:10   #16
Member
 
Landlockedpirate's Avatar
 
Country: UK - England
Town: St Helens
Boat name: Wine Down
Make: Maxum
Length: 8m +
Engine: Inboard
Join Date: Apr 2012
Posts: 934
Quote:
Originally Posted by 69cmw View Post
If your insurance company insure a bigger engine, what's the problem?
Because when you take out the insuance most companies dont do any checks i.e. You could insure a slat floor 2.4m Zodiac with a 40hp engine on it no problem.

But in the small print it will say the engine must be suitable for the boat, so when you have an accident then they will do the checks and you will be up a creek........
__________________
Landlockedpirate is offline   Reply With Quote
Old 28 April 2014, 17:18   #17
Member
 
Country: UK - England
Town: East
Boat name: Seaflyer
Make: Humber
Length: 6m +
Engine: Evinrude
Join Date: Feb 2014
Posts: 199
If you insist on fitting an engine of higher rated power output than the boat manufacturers Maximum rated horsepower then ask yourself this: - if anyone gets injured from your boat/engine, what defence will you give in court for overpowering it because seeing how the legal system works I for one would not put myself in your shoes. This is before we even go down the insurance route as previously mentioned.

Just one more thought, I have seen on this thread about reference to engine weight on the transom, that is only one consideration. Think of the power of the outboard trying to twist your motor/transom from the back of your boat. The manufacturers have calculated how much force can be applied to the transom SAFELY.
I have seen a 25HP clamped to a SIB (not bolted through) when put through a tight turn twist itself off the transom, the only things stopping it become a liberated anchor was the Teleflex steering and the remote cables - Oh and the guy clinging on to it for his life!
__________________
Seaflyer02 is offline   Reply With Quote
Old 28 April 2014, 17:26   #18
Member
 
Landlockedpirate's Avatar
 
Country: UK - England
Town: St Helens
Boat name: Wine Down
Make: Maxum
Length: 8m +
Engine: Inboard
Join Date: Apr 2012
Posts: 934
Quote:
Originally Posted by Stevenmb View Post
Thank you for your replies, as a novice to boating ( been out couple times with my mates) I presumed that all 30hp engines are the 25hp engine just without them being restricted. The engine I have is a 2 stroke 2 cylinder ( 2 spark plugs ( sticker says one is16hp and other is 14hp) ). I also I understood that the transom can often hold more weight etc however they lower it as a way to cover their self from liability if a transom was to fail. My example of this is my boat is roughly 3-4 metres which states it holds a 40ph (2 stroke back then) however the newer boats which are the same size are rated to a max of 30hp( ie the hon waves ) however most of the avon sports only go up to 25hp. So being the same boat pretty my question is surely it wouldn't effect the boat at all as it's only 5 hp more then it states? I realise in terms insurance it might be an issue however I would have asked that once someone gave me there experienced knowledge about the issues it might cause. I'm sure plenty of people have put a bigger engine on a boat then stated. I obviously I wouldn't put a 50hp on a transom maxed at 25hp but surely a 30hp on a 25 wouldn't be that bad?

In a lot of cases it wont be a problem at all, but you need to have the experience to understand that. Older boats were much, much heavier than modern PVC sibs and so sticking a 40hp on an old Avon with an over engineered transom that weighed the same as the Forth Bridge wasnt a problem.

I will try to give you an example. The Zodiac Futura Mk2C Fastroller is rated to 25hp. With 1 person on board and a 25 the boat becomes a rocket ship, right on the edge of safe performance for a sib. It even starts to chine walk on the speed tubes if you get just the right amount of popple on the water. Stick a 30hp on it and it can go wrong very quickly, throwing the helm or even flipping the boat.

But at the other end of the spectrum, putting a same weight 25hp motor (instead of the stated 20hp max) on a fully loaded new Honwave T35 wouldnt be an issue (insurance accepted).

My dad over engined all of his speed boats in the 70's and 80's, mainly because we needed the performance for barefooting, but back then insurance was easy and 'Where there's blame there's a claim' firms didnt exist. These days its just not worth the risk.

Of course you could just ignore the advice and do it anyway .......

__________________
Landlockedpirate is offline   Reply With Quote
Old 28 April 2014, 18:42   #19
Member
 
simon23's Avatar
 
Country: UK - England
Town: liverpool
Make: tohatsu6.1 one desig
Length: 6m +
Engine: mariner 125hp
Join Date: Jan 2012
Posts: 357
Has anyone ever overpowered a boat,been honest with the insurance company and got cover that will pay out?
__________________
simon23 is offline   Reply With Quote
Old 29 April 2014, 02:31   #20
Member
 
Country: UK - Scotland
Make: Destroyer 5.5/Ring18
Length: 3m +
Engine: Yam 90HP/Yam200HP
Join Date: Jul 2009
Posts: 447
Yes, twice over the last 16 years, both times they paid out satisfactorily and that was for 2 theft claims.
__________________

__________________
69cmw is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 06:59.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.