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AI turns into the wind
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Author:  Geoff [ Mon Mar 17, 2008 2:16 am ]
Post subject:  AI turns into the wind

I have had my AI only a week, and had 3 sails. On every occasion, I have found wind gusts cause the kayak to point into the wind, and ignore the rudder. This does not happen all the time, but it happens often enough. My AI is fitted with the newer enhanced rudder.

I initially found this was worse to one side, and after talking to the dealer, I tightened the cords on one side of the rudder. It appeared then to be turning the same amount to both left and right. But I also noticed that if the down cord is cleated and tight, it works to limit the max turn of the rudder, in both directions.

Can anyone tell me how many degrees of rudder movement is expected, as I am wondering why I am having a problem, that no one else has reported. I am sailing in 10 to 15 knots of wind, with swell and chop. But its quite irritating when the kayak makes off by itself. I have found pumping the rudder can help, and will sometimes regain control but basically I am sailing without control, for maybe 5 to 10 seconds.

Geoff.

Author:  mmiller [ Mon Mar 17, 2008 9:04 am ]
Post subject: 

The rudder is coming up maybe? Did you get the rudder control line retrofit?

If it overpowers the rudder with all the current stuff... you have to reef the sail. At some point you are going to get over powered regardless of the rudder setup.

Author:  Geoff [ Mon Mar 17, 2008 2:43 pm ]
Post subject: 

mmiller wrote:
The rudder is coming up maybe? Did you get the rudder control line retrofit?

If it overpowers the rudder with all the current stuff... you have to reef the sail. At some point you are going to get over powered regardless of the rudder setup.


Hi Matt,

No the rudder is not coming up. I have a brand new Kayak, with the cleat on the line to lower the rudder. I am disappointed if its "over powered" as it sure does not feel that way. I have never experienced anything similar with my H14, which I sailed for over 20 years. I really wanted to know if the rudder is meant to go "hard over" both left and right, because it seems mine does not move the last 5 or 6 mm which would deliver a lot of movement. Or is it considered it does not need to be hard over?

Geoff.

Author:  sunjammers [ Mon Mar 17, 2008 3:41 pm ]
Post subject: 

I've found that over steering causes the rudder to stall out. You can manually turn the rudder by hand and see if it has any more room to turn. I get people in the shop all the time thinking there rudder should turn farther, we simply show them the rudder housing is hitting the kayak.

Author:  KayakingBob [ Mon Mar 17, 2008 4:28 pm ]
Post subject: 

Here in Maui, in 15k winds with chop and swell, if the rudder hold-down is not real tight the rudder will slightly pop up and loose 10-20% of control. To help keep the rudder REAL tight, I adjust the pull-down line so it starts lowering the rudder as soon as I start pulling it, (not the 2-3" of pull before it lowers). This way I can use the cup holder with my thumb to give it an extra pry. It makes a difference.

Also at 15k your sail should be reefed back at least 1' (just about to the tell-tails) or the boat will be overpowered and sail slower. With the newer sailing rudder (with the notch) the only indicator that you have too much sail out is the leeward ama burying.

Kayaking Bob

Image

Author:  mmiller [ Mon Mar 17, 2008 4:34 pm ]
Post subject:  Rudder hard over

The rudder going hard over would help with steering at very low speeds, but when powered up, there should be very little motion needed. I suspect over steering and cavitation may be a cause of loss of steering.

Next would be sheeting hard before the boat gets moving. Oversheeting can cause the boat to crab sideways and cause loss of steering. This is the same in a sudden gust. Best to sheet out a bit and get the boat moving, turn away from the wind and then slowly sheet back in.

Daggerboard position? Try different angles.

If truly overpowered, the AI goes faster when roller furled than with full sail, so you can try rolling up a bit of sail. Try also using a bit of pedaling to get it moving if steering is an issue.

Author:  Geoff [ Mon Mar 17, 2008 10:54 pm ]
Post subject:  Re: Rudder hard over

mmiller wrote:
The rudder going hard over would help with steering at very low speeds, but when powered up, there should be very little motion needed. I suspect over steering and cavitation may be a cause of loss of steering.


Yes I wondered about cavitation.

mmiller wrote:
If truly overpowered, the AI goes faster when roller furled than with full sail, so you can try rolling up a bit of sail. Try also using a bit of pedaling to get it moving if steering is an issue.


I have tried pedaling to regain control, and although it reduced the turning into the wind, it did not specifically regain control. I will try furling, and watch the leeside ama.

I don't have a projector to accurately measure the rudder movement, but I see it is still unbalanced. I get about 20 degrees to right, 25 to left, and at about 40 the rudder will hit the body.

If I adjust one of the cords, must I move the other side the equivalent but opposite amount? Or are they independent.

Geoff.

Author:  Roadrunner [ Mon Mar 17, 2008 11:54 pm ]
Post subject: 

Depends on how loose the lines are. With the rudder down, take up any slack by tightening the side you want more angle on. Then if you still need more, you'll have to loosen the opposite side. I like the lines tight so the rudder is accurately positioned for crisp handling. If you still need more control you can try adding a winglet to the bottom.

I had a similar situation to yours -- needed a little more right rudder. When I tightened up the slack, it was just about right.

Cavitation, stall and loss of speed? Easy does it or it will turn into a big speed brake. Have a look:
Image

BTW, that's about how much deflection you should be getting on either side. You can hinge a couple of small sticks together with friction to check if your angles are similar, using the keel line as a reference..8)

Author:  Geoff [ Tue Mar 18, 2008 1:04 am ]
Post subject: 

Roadrunner wrote:
Cavitation, stall and loss of speed? Easy does it or it will turn into a big speed brake. Have a look:


I am having my problem after I lose control of the direction, so I am not applying much rudder, and the boat suddenly points into the wind, still going pretty well, but just not responding to rudder.

Roadrunner wrote:
BTW, that's about how much deflection you should be getting on either side. You can hinge a couple of small sticks together with friction to check if your angles are similar, using the keel line as a reference..8)


No, I don't think I am getting that much. Looks like 30 maybe 35 degrees?

Geoff.

Author:  Chekika [ Tue Mar 18, 2008 6:45 am ]
Post subject:  Thanks for the advice

Wow, lots of good advice here. Thanks.

Keith

Author:  Geoff [ Wed Mar 19, 2008 12:56 am ]
Post subject: 

Well after all that good advice, I have to confess I did not follow it. If I get my just desserts, so be it.

I decided to adjust the rudders, and to move them to the position I wanted on full rudder, which was just off hitting the body. Then I adjusted each cord to suit. So I move the rudder handle to full over (either left or right) and move the rudder where I want it, and tighten the cord. Repeat on other side.

Now it seems I have far more rudder movement than I had before. If there is a flaw with this approach, I will find out at the weekend, wind willing.

The difference with this approach is I was not setting the neutral straight ahead position, but the full lock position.

Author:  gwiz [ Fri Mar 21, 2008 12:22 pm ]
Post subject: 

I just got back from getting the new up/down rudder system. It is a big improvement as far as getting the rudder up and down but it won't lock it down any better than the other way except that it does pull it back into position after stress is removed.

I will be drilling a small hole in the bottom leading edge of the rudder and using a bungee to the bottom of the yak as well. I know I can still use the plastic lock down screw but I never had any luck with that holding either.The bottom bungee holds better but still allows the rudder to kick up before breaking anything. I know this for a fact because I have unintentionally tested it a couple of times.

gwiz

Author:  Geoff [ Fri Mar 21, 2008 11:03 pm ]
Post subject: 

Geoff wrote:
Now it seems I have far more rudder movement than I had before. If there is a flaw with this approach, I will find out at the weekend, wind willing.

The difference with this approach is I was not setting the neutral straight ahead position, but the full lock position.


Yup, based on today it is 200% better than it ever was, and I had the sensation of not needing to use much rudder ever, instead of the sensation of never having enough rudder. The wind was prob 8 kt gusting to 12/15 so its not a perfect test, but I noticed that even pedaling, without sail, and the rudder hard over I can now HEAR the rudder, just like in the pic above.

And a follow-up today. Its just fine now. All it needed was the ability to turn fully left and right. Obviously assembled in the factory a bit slack.

Geoff.

Author:  yakman [ Thu May 08, 2008 1:10 pm ]
Post subject:  lossen up the sail

I find that if I loosen up the sail even a inch or 2 before the turn - I get back the rudder

When your in high winds you have trim the boat for better performance

I have noticed that adjusting the centerboard angle helps a little

But clearly the single best thing to do is furl in the sail a little, like Matt said most people are furling in the sails to achieve faster speeds anyway

Are you using the screw on the rudder? that should keep the rudder all the way down

Author:  Geoff [ Thu May 08, 2008 1:57 pm ]
Post subject:  Re: lossen up the sail

yakman wrote:
I find that if I loosen up the sail even a inch or 2 before the turn - I get back the rudder

When your in high winds you have trim the boat for better performance

I have noticed that adjusting the centerboard angle helps a little

But clearly the single best thing to do is furl in the sail a little, like Matt said most people are furling in the sails to achieve faster speeds anyway

Are you using the screw on the rudder? that should keep the rudder all the way down


Hi Yakman,

All that advice was not the issue. My rudders were simply not turning far enough, and now they are great. No more problems. I also found that for me, setting the left and right position, rather than setting the centre position made far more sense. After all there are two ropes to adjust, the left and the right. The centre position simply occurs when they switch over. And as I said earlier, I now have the sensation of not needing much rudder, whereas before I never had enough.

I don't doubt that there are issues when over powered, but that was just not the problem. The rudder just did not turn far enough as delivered. My yak is an 08 model, I think. Has big rudder, cleat and pull up/down ropes.

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