Big motor - small boat

[goeasy123]

What are the implications of putting a 15hp 2-stroke motor (relatively light) on a 2.5m roll up/airdeck/keeled Highfield design for a 6hp 4-stroke, apart from not gunning it?

I have an opportunity to buy the motor, but can't get a bigger RIB to suit it for a while, so I've got to use my existing 2.5m dingy.

 

[B27]

The weight of the motor will twist the transom.
The thrust of the motor will twist the transom the other way!

A 15HP 2T may not be much heavier than a 6HP 4T.
If it's short-shaft you might get away with the thrust.

If you potter around with the 2T it might oil the plugs.

 

[jwilson]

I once submerged the transom of a small wooden dinghy by giving a 4 hp motor full throttle. Damp experience....

Or you might just go very fast.

 

[Tranona]

Maximum is 6HP DO NOT EXCEED

You will be a danger to yourself and others. There is a reason why the design limit is 6HP and if you attached a 15 you would find out why very quickly as the boat will invert as soon as you open the throttle.

 

[PCUK]

Then again, worth a try!

 

[Aja]

What are the implications of putting a 15hp 2-stroke motor (relatively light) on a 2.5m roll up/airdeck/keeled Highfield design for a 6hp 4-stroke, apart from not gunning it?

I have an opportunity to buy the motor, but can't get a bigger RIB to suit it for a while, so I've got to use my existing 2.5m dingy.

Is there a category in the Darwin Awards for this?

 

[rogerthebodger]

You would need a tiller extension so you can operate the engine while sitting on the bow

 

[Boathook]

What are the implications of putting a 15hp 2-stroke motor (relatively light) on a 2.5m roll up/airdeck/keeled Highfield design for a 6hp 4-stroke, apart from not gunning it?

I have an opportunity to buy the motor, but can't get a bigger RIB to suit it for a while, so I've got to use my existing 2.5m dingy.

You could try it but any insurance would be invalid if something goes wrong. You would / should be ok with 8hp but would need to be careful. Again insurance ....