Engine Powered Kayak Idea

[ShipOfFools]

Here's an idea i had to expand upon the previous thread on inflatables. Do you guys think this is possible?

Buy a kayak then have a custom motor mount built to accept small to mid sized outboard, say 2.5 HP to 6HP weighing between 20 and 50 lbs. The kayak would be big enough so it won't look ridiculous or have the bow up in the air. Perhaps install pontoons/floaters on each side to lengthen the boat length.

Would it be possible to achieve a speed of 20 to 30 MPH with a setup like this?

Max weight would be 150 to 200 lbs including both boat, motor, and accessories, and could be towed on my bike trailer. Max length of 12 to 14 feet boat.

[motion30]

30mph in the kayak? sounds like an e ticket ride to me

[Psy at SEA]

In South Africa we don't play around, here the boys are hardcore. Check Stealth Products Power Fisha 16 - STEALTH PERFORMANCE PRODUCTS


Specifications:

• Best Feature: Speed, Stability & Performance
• Conditions: Freshwater and Open Ocean
• Length: 4.76m
• Width: 1.29m
• Weight: weight without fittings, hatches etc – approx 58kg
• Max Angler Weight: 2 people- 270kg
• Capacity: 550kg
• Max HP – 15hp or outboard 45kg and under
• Stability: 10
• Speed: 10
• Glide: 5
• Manoeuvrability: 5
• Surf Ability: 5

[kapnd]

For the speeds you mention, you will need a planing hull.
Driving a displacement hull above design speeds can be quite dangerous.
For just putting along, a single outrigger with a motor mounted on the ama will do just fine.

[ShipOfFools]

Originally Posted by kapnd

For the speeds you mention, you will need a planing hull.
Driving a displacement hull above design speeds can be quite dangerous.
For just putting along, a single outrigger with a motor mounted on the ama will do just fine.

Thanks assuming i get a planing hull, would outriggers or pontoons make it more stable at high speed or less?

[Psy at SEA]

https://www.youtube.com/watch?v=sWsUKocplPM

https://www.youtube.com/watch?v=nJYj9RKYdpE

[kapnd]

Originally Posted by ShipOfFools

Thanks assuming i get a planing hull, would outriggers or pontoons make it more stable at high speed or less?

I don’t think outriggers would make it less stable, assuming that the outrigger would be engineered to match the speed of the main hull.
A planing hull would likely be built to accept an outboard on the centerline anyway, nullifying the need for an outrigger.
Do a google search on planing plastic kayaks or something similar, there’s lots of info on the net.

[Cheechako]

ELectric, lithium batteries. Tiny prop... or... maybe a simple water jet system? That's just a tiny prop (impeller) situated in a Venturi to create thrust increase like a jet engine does. A kayak is so narrow and light with a long waterline it shouldn't take much I wouldn't think...

[HopCar]

Won’t go thirty but it will plane with 2.5 horsepower and it will tow behind a bike.
https://youtu.be/3A9_5BMcI5Y

https://youtu.be/FVOVfgw_vpM

[disputin]

Why limit yourself to just an outboard. How about jet powered?

https://www.youtube.com/watch?v=89-SerAttxE

Sean

[ranger58sb]

Originally Posted by ShipOfFools

Buy a kayak then have a custom motor mount built to accept small to mid sized outboard, say 2.5 HP to 6HP weighing between 20 and 50 lbs. The kayak would be big enough so it won't look ridiculous or have the bow up in the air. Perhaps install pontoons/floaters on each side to lengthen the boat length.

Would it be possible to achieve a speed of 20 to 30 MPH with a setup like this?

Max weight would be 150 to 200 lbs including both boat, motor, and accessories, and could be towed on my bike trailer. Max length of 12 to 14 feet boat.

Probably easier to fit an outboard or electrictrolling motor to a square stern canoe. Displacement speeds. Going too fast in such a rig threatens stability (ask me how I know that).

Our 19' model weighs 116-lbs, and the 5-hp 2-stroke outboard we had at the time was 46 lbs. 5 hp was a bit sporty. Plus fuel. Plus stuff. More weight in the boat while underway is a good thing.

-Chris

[Dave_S]

This is what you want

https://youtu.be/AF9nBjgcX3E

[Brewgyver]

Originally Posted by ShipOfFools

Here's an idea i had to expand upon the previous thread on inflatables. Do you guys think this is possible?

Possible? Certainly. Survivable? Open question. Enjoyable? Probably not for very long.

My question is why would you want to go 20-30 in a kayak?

Check youtube for videos on yaks with trolling motors. I did one myself, made an offset mount with a piece of large aluminum channel (upright from a server rack), a couple of heavy angle brackets, screwed into top of yak hull just behind the seat. 30 lb thrust trolling motor mounted on starboard side, battery strapped in just forward of crossbar that supports fishfinder. It would do about five knots according to smartphone speedo app, and that was more than enough for me. I used the spare battery I had on hand, which was a group 27, and really too heavy for the purpose.

If you want something relatively light, towable on a small trailer, and able to really zip with say a 6 hp outboard, without killing yourself, look for a good deal on a Hobie Adventure Island.

[hamburking]

While visiting a nearby island recently, I met a local man who had come to the island in a powered kayak. It had some sort of inboard engine mounted centrally. He climbed into the kayak, pulled a starter cord, and a very loud engine roared to life. Once pointed in the right direction he put it in gear and flew out of there on full plane. I got the feeling he had very little control at that speed. I thought it was nuts, but he sure went fast. He had told me it was home built, his own design. From the outside it looked like a regular kayak...no outriggers or extensions...the motor was entirely inside.

[hamburking]

I built a bike trailer to tow around my laser sailboat. Mostly lumber, no welding or special skills. Simple and sturdy. Worked very well. Total loaded trailer weight around 200 pounds.

So towing a kakak/motor/gear behind your bike should be no trouble at all.

The golden rule is that the tow vehicle (that's YOU and your bike) must weigh MORE than the total loaded trailer.

I would tow the boat to a local waterfront park, disconnect the trailer from my bike, and roll the trailer by hand to launch on a rocky beach. Haulout was a little tougher, being uphill and everything wet (heavy).