Viking/Force 125 Setup

I have a 1978 Viking with a 1988 Force 125hp turning a 13x23 stainless prop.  Motor is bolted directly onto the boat and this puts the propshaft 4.5 inches below the pad.  It runs around 55-60 mph if I take a chance and burry the RPM needle in excess of 7000.  I have two 6-gallon tanks and 2 batteries in the back.  Stock single cable steering.  I use the boat for skiing and cruising. 

-It will not plane out with 4 people in it unless one person sits on the front.  Nose comes up, boat plows.

-The front end bobs up and down badly when turning and at certain speeds.

-Severe chine at top speed.

Also, I would like greater top speed but still have the ability to pull a skier up. 

What do you think of relocating the fuel tank to the nose, and is a kit available for this?

What do you think of a hydraulic jack plate and which would you recommend? 

Thank you for your help!


I would be happy with what you have. The jack plate will do nothing for you with this motor. I would look at the tach though. The motor would be in pieces if it was turning 7000. A 23 at 55-60 is somewhere in the upper 5000 range, so I would say the setting is off. The tank in the nose will kill the top end. Look at a cav-plate planning device to help hole shot. The force is not noted for its punch, so it needs help there.




Please submit whatever questions you have to  All questions and answers selected will be displayed on this page as they come in.  Note: though all boaters are welcome, priority may be given to I.H.R. members.  Randy can not be held responsible for any advice given.  Though his information and expertise is second to none, he has no control over what you do with your boat.  It is up to you to boat safely and act responsibly, and his advice is only to be used as a guidance for your high performance boat/motor of which you are the one responsible for the risks involved.

Mark C.


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