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PostPosted: Mon May 26, 2008 7:06 pm 
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Joined: Sun Aug 06, 2006 5:06 pm
Posts: 59
Location: Evansville, IN
Anyone care to share their experience using the AI in rivers? I live on the Ohio, and near the Wabash rivers. I've sailed a Hobie Bravo and Wave in the Ohio, in the summer, when the current is almost nonexistent and it is like a lake. You barely notice the current.

But in the Spring, when the rivers are higher, the current is a factor.

Arranging a downstream shuttle isn't a viable option, so I need to be able to go upstream --- and then return. How strong a current do you deal with, and how best to judge its strength?

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PostPosted: Wed May 28, 2008 7:42 pm 
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Joined: Sat Jul 14, 2007 11:46 am
Posts: 76
Location: sacramento
Try sevylor motor search. Side mount in rod holders with 1 1/4 # 40 or 80 pvc. and 2x6 lash where required. Hold down total yak weight under 300. Sufficent power for current. Steady low speed or short burst for 3 hrs. or 8 miles. With some breeze and pedals steady 3.5mph in any direction. The motor will allow good parking control at lunch time. Thats how I use it. No shallow water. 10"- 12". The long shaft is easy to cut short if you like. For longer trips use 28 kota & sealed battery. Kota set up does add weight but also time and miles. I mount one kota motor thru the pedal slot. I often use the sevylor side mount.


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PostPosted: Sun Jun 01, 2008 9:16 pm 
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Joined: Thu Aug 16, 2007 2:25 pm
Posts: 1965
Location: Central Coast NSW Australia
G'Day Bruce,
A good way to judge the current is to use the Miragedrive speedo pitot tube in conjunction with a GPS. Roadrunner posted about it here:
http://www.hobiecat.com/community/viewt ... ight=pitot
I use both tube and GPS and find the combination useful. Current isn't really an issue in the AI if the wind is right of course. Turbo fins are a real improvement when the wind dies and you're fighting a current by yourself. I have been in our local tidal current a few times and have made steady progress against the current with turbos. The AI ama's when windless and level don't seem to add much drag.


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PostPosted: Fri May 21, 2010 2:02 pm 
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Joined: Tue May 27, 2008 7:01 am
Posts: 5
I do fair amount of AI sailing/peddling on the Gatineau and Ottawa rivers.

Rule #1: NEVER trust your rudder if you plan on getting near cement bridge ramparts, rapids, etc. I believe in strange fast-whirling currents, the effect can sometimes cause your rudder to not work or to not turn or to actually turn your boat the opposite direction. This can be fun, but not if you end up hitting rapids or a piece of cement. If you plan to do anything risky like bypass rapids, etc. then you should raise your rudder, remove your daggerboard, keep your fins against the hull (or remove) to protect against shallow rocks. Not having a rudder means you are a raft floating without any "front". A strong paddle can be used as a rudder though the forces are very large and you can easily lose the paddle. (Paddle leash recommended). Raising your rudder means that you understand that the rudder is 0% functional. This is better than using a rudder and having it become 0% functional at a dangerous time. I don't believe this is a flaw in AI design, but it is just a natural consequence of the physics of the river.

Rule #2: Start your journey by going upstream. Then you can relax on the downstream trip. ALso if you have tech problems, you can drift back to your start, but not vice-versa.

Rule #3: Tack Tack Tack: The river current can be strong enough as you go upstream (and upwind) that you can end up in the same spot even after travelling "forwards" and tacking. Gybing generally causes a huge loss in river position. Turbo pedals are recommended.

Rule #4: Understand the rules of large freighters/ships in your river. Avoid their areas like the plague. A bit of fog could reduce visibility to zero. (This is more applicable to large rivers like St. Laurence Seaway). Avoid hydro dams, rapids and other dangerous obstructions.

Generally river kayaking is very rewarding and safe. The shores are always pretty close, and there are no tides or massive waves. Surf is rarely an issue. I enjoy dusk when the beavers start "playing" with you. Also there are many bats that come out to feast on insects.


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PostPosted: Sat May 22, 2010 2:50 am 
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Joined: Wed Apr 07, 2010 9:49 am
Posts: 403
Location: Point Lookout, Maryland
We've been using our yaks on some of the local rivers around here (Potomac, Monocacy, Severn, South and others). None of them have any commercial ship traffic, but they do have motorboats and jet skis to deal with (the jet skis and the idiots driving them are the worst). The Potomac also has a number of low-head dams, water intakes, snags, rapids and falls that can be treacherous to be around with sit-on-top kayaks, not to mention hidden rocks and wild currents in places.

We've found the Mirage drives to be the *best* thing we've ever used for going upstream in a current - much better than using a paddle. As mentioned by others, the hidden currents can really be a surprise when encountered - as in WTF-just-yanked-me-around kinda surprise. We been able to crawl upstream at a slow but steady pace, then turn around and go downstream at the same pace at over 7 MPH as measured by GPS. Also as mentioned by others, there will be times when the rudder will be affected by hidden currents or boils and not respond as expected.

So far we've never been dumped in the rivers we've been on, but the effects of the hidden currents have been so unnerving that we make certain to *wear* our PFDs anytime we go out on them. We also constantly scan the water ahead for perils - the low-head dams are particularly dangerous because they can be so hard to spot.

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    2010 Tandem Island
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PostPosted: Fri May 28, 2010 9:44 pm 
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Joined: Sat May 22, 2010 3:53 pm
Posts: 110
Location: Sunshine Coast, Queensland Australia
I find it's always best to try and judge what's ahead based on land formations, bends in a river etc.

Other river craft can also create a bit of a problem.

A while ago we were out on the Noosa River (Australia) and had to wait for a vehicle 'Cable Punt' to cross in front of us. There's actually 2 Punts running when the demand exists and the river is about 100 yards wide at this point.

Anyway, from a stationary position in a spot clear of the Punts we started (to avoid the other Punt coming back...real quick turn arounds) and got caught in the swirl left behind by the previous Punt. We did a complete 180 before we could get clear.

In hindsight I think we would have been better off a bit further back and approaching the crossing between the Punts with a bit of a 'run up'.

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