Author Topic: Moveable Seat - Experiment  (Read 769 times)

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Offline Californiamokai

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Moveable Seat - Experiment
« on: November 14, 2020, 08:30:27 PM »
Often wondered about having the flexibility to incrementally change the seat location while trying to get to plane.  Completed the experiment of changing how my seat fastens down while having the ability to move from stern to closer to bow.

Supplier of hardware discovered to do this for Jon boat bench seating. Retrofitted to to my vintage 2006 Mokai by doing some minor slotting of the suppliers support to existing post wise support ribs of our Mokai. No drilling to Mokai necessary and whole support system can removed in one piece.

What I learned.  Seat fasting very good and secure regardless of seat location while moving stern to bow, no noticeable improvement of performance while incrementally increasing speed (center of mass of boat topic), might have taken speed down a bit due to moveable seat weighing 6 lbs more then original fastening.

End result of experiment.  Removed all and went back to my original permanent fastening of seat.  Why?  Interfered with my ability to safely stand why fly casting and line management issue with entangling fly line in new supports.  Maybe others will find this info useful in their applications.  Tight lines, John

Listing of Jon boat part: SWIV SP-15200 Seat Ext Jon Bt 2pk, One Size, SP-15100 SWIV Seat Mt Jon Bt, Unspecified, One Size
« Last Edit: November 14, 2020, 08:32:14 PM by Californiamokai »

Offline Hillbilly

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Re: Moveable Seat - Experiment
« Reply #1 on: November 15, 2020, 11:35:08 AM »
Great post, John.  Thank you.  I have used that slider system on several jon boats but your use of it here is a great idea.  It does seem the added weight is why you didn't see a speed increase.  I know that I gain a full mph when I slide way forward at open throttle on my boats.

Offline Painlesstom

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Re: Moveable Seat - Experiment
« Reply #2 on: November 15, 2020, 09:05:44 PM »
The added weight is probably why there was no increase in speed. Like George, all of my Mokais will gain 1 mph by sitting at mid cockpit with my legs straight out in the bow. Come off plane though and you will likely unload the pump and require sitting back before it will reprime. I like your sliding seat idea, but never did it because of how weight sensitive these boats are. Many things I've decided to go without in the name of weight savings. haha



Offline Mokai Dreamin'

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Re: Moveable Seat - Experiment
« Reply #3 on: November 15, 2020, 09:37:22 PM »
I plan on installing a sliding platform later this winter. I chose this one off of Amazon:

I have the ES-Kape 2.0, so kind of an apples to orange comparison between earlier models.

At the end of last year I found I could gain 2 mph by leaning forward and/or shifting my body forward on the seat once I was up on plane.

I've also spoken to a number of people that have larger jet boats, and how they were able to gain up to about 6 mile an hour by trimming their boats. We're talking about 60/40 hp jets here, but concept is similar. In talking to these other guys  I learned that starting out with the motor trimmed all the way down was best, and then they gradually trimmed them up as the boat came up on plane.

I reasoned a similar thing could be done by shifting the balancing point in the Mokai. Some boat seem to take forever to come up on plane, and the only way to even get them on plane is by shifting a bunch of weight forward. The other option is trim tabs. In each case it's a balancing act. Equalize the force via trim tabs or shift weight. More HP doesn't help at the start either.

So, I thought it worthy of more exploration particularly in the 2.0 which is a tough boat to get on plane. All of the magic seems to happen in the 2.0 once the boat gets up on plane. Otherwise, the stern tends to just sink and shovels into the water and creates a braking effect.  I'm hoping  that by finely tuning the pivot or axis point it will make a difference in how quickly the boat will plane. At the very least one should gain some speed once the boat is on plane. Either way, there is something to be gained.  Well,  that's the theory at least.  I won't know the results of my test until next spring, but nice to see somebody else was playing around with the idea at least.