Any experience running fast shallow Appalachian mountain rivers...

[oleredbeard]

Im attempting to build a jet jon and wanted to know if anyone has any experience with running this type of water in one. Its pretty brutal stuff that as far as I know only sees canoes and kayaks.. I have tried just about everything known up to this point from mud motors with rock guards welded on the sides to driving a truck down to the takeout point and riding a bike back and hiding it in the woods while I float down.. Id like to build a jet jon to run up the river and fish down... However, I know of nobody locally that has done it and most of the people that do don't hit the upper areas of the Clinch river. It varies from deep pools and slow water to shallow fast water less than a few inches deep with boulders and rocks everywhere. Very little sand on the bottom except in the slower parts and mostly just a mountain river.
So... before I get started on another build and dump a ton of money into a fruitless endeavor I wanted to ask your opinion on if it would even be worthwhile or if I would just tear the crap out of the build.

 

[overboard]

Less than a few inches deep with boulders and rocks sounds like it will tear the crap out of a boat sooner or later.
I think they make a polymer sheeting to install on the bottom of the hull that would add a lot of protection, but I am not familiar with it. I live between 2 rivers that are the same as you are describing, lots of jets are used on them, some of the boats I have looked at had hulls that were extensively damaged from hitting rocks.
I would also suggest a MV with a tunnel hull to get the motor tucked up as high as possible, like most jet owners say, it's not if you hit, it's when you hit, and guaranteed you will hit under those conditions!
You also need to get to know the river and exactly where you need to be, once you learn that, you can pretty much run it at full power without damaging anything.

 

[FuzzyGrub]

I'd ask yourself, can you navigate through those bolders, etc, at 20mph? Jets don't turn on a dime, either.

They line the bottom with UHMW. Require a jon boat with thicker aluminum to support it. Not typical of your average jon boat. Its bolt through, hundreds of them. On thinner metal boats, they use specialized coatings, but not going to protect you as good.

Since you don't see others doing it, probably a good reason for it.

 

[thill]

They run them over in the valley, and they are typically 14 or 16' wide-body jon boats with a 15" transom modified with a tunnel hull fabricated in the bottom, a raised transom for a jet motor, and the bottom covered with panels of 1/2" high density plastic. Most I see are running 40-60 HP motors, but some guys are running 90-115's with a jet on the bottom to go really fast.

Looks like fun, but not my thing.

 

[Vol423]

I am a licensed boat manufacturer in East Tennessee. I sell almost exclusively outboard jet boats. I don't build them but have them built for me. Any major river in this region will see jet boat usage. The Clinch, Holston, Nolichukey, French broad and Tennessee rivers in Tennessee and larger rivers in Virginia and NC will have jets. In general, you need about 12" of water to take off and a good boat will run in 3-4". Most of my boats have .100 to .250" thick bottoms with no UHMWPE.They have a tunnel that keeps the jet outdrive above the boat bottom to avoid damage to the outdrive. If you aren't seeing jets where you are it's most likely there isn't sufficient deep water for takeoff and too many rocks. Check out River Road boats in Lynchburg, VA for examples of boats with UHMWPE clad bottoms. They use 175 HP outboard jets to push 15 foot boats. Jet drives take away 1/3 of the horsepower of an outboard, so a 90 HP motor delivers 65 HP at the jet drive. It's hard to get much over 30 MPH out of a jet boat, even with outsized motors. In general, a flat bottomed isn't best for a jet drive. You need a slight V shape of 5-6 degrees to shed entrained air away from the jet intake. Also never build rocker like a drift boat bottom into a jet hull. That will make a boat porpoise in the extreme. Transom angles should be at least 20 degrees as porpoising in jet boats is common. I suggest buying a used jet boat and learn from it first before trying to build one. I have seen many amateur abominations just that didn't work.

 

[Pawatch]

I run a river jet. 1654 flat bottom with a tunnel, 90/65 jet.
195 bottom with 1/2" UHMV over top of that.
Google Snyder jet boats.

 

[Kismet]

I'd ask yourself, can you navigate through those bolders, etc, at 20mph? Jets don't turn on a dime, either.

They line the bottom with UHMW. Require a jon boat with thicker aluminum to support it. Not typical of your average jon boat. Its bolt through, hundreds of them. On thinner metal boats, they use specialized coatings, but not going to protect you as good.

Since you don't see others doing it, probably a good reason for it.

Last Century, I worked for a company with 6 plants scattered around the U.S. Part of the work involved putting faces of workers' personal pursuits in front of the rest of the Corporation. One plant was in Chattanooga, TN.

I was tipped to a guy who ran whitewater rivers in canoes. His boats were filled with polyethylene rigid foam from stem to stern, with marginal space for the paddler. In the interview for the story, I asked why. He explained that often, maybe most often, the canoe was underwater with only his torso above the surface. Even so, he said, the helmet, life jacket, and gloves sometimes just barely protected his body and frequently saved his life. These were rivers which were inaccessible without special equipment, and the pictures he showed were like seeing a boat and paddler in a narrow blender which was propelled downstream at 25 miles per hour.

Never in our discussion did we go far into motorized craft; he said his reaction time wasn't sufficient to survive the maneuvering.
There is a reason you can't find anyone who's done it.

The canoe was suicidal; a craft such as you are suggesting would be fatal.

Please reconsider. Best wishes.

 

[Striper57]

I'm assuming you must be near the headwaters of the Clinch up in Virginia to see water like that. I haven't run the Upper Clinch personally, but I know some other jet boat guys that run the Upper Clinch in TN, so I am guessing you are upstream of those guys.

 

[Creekchub]

I run the new and James river in VA. My boat is a war eagle stick steer with a 60/45 jet. I can run most sections is the river but where there are stair stepped ledges.

On plane, I’m running in inches of water. I’ve never measured but I’ve clinched my butt checks many times.

Here’s a few options:
1) a tank of a boat with uhmw like others mentioned. Expensive but very impressive. My cousin has a James river jet and it’s impressive.
2) get a thin hulled jon with as light of a jet you can find. Probably looking at an older 2 stroke but don’t expect blazing speeds but you don’t need. This set up would allow you to man handle the boat in super shallow spots.
3) check out hog island skiffs. It’s basically a kayak on steroids. Very impressed boats with a jet. Slide very easy over rocks. I had one and miss it in the shallow summer river levels