My wife and I have been using sea kayaks for the last several months. In that time we have bought a “vintage” WS Cape Horn 170 and a AquaTerra Sea Lion (17’), both plastic. We find the Cape Horn is both difficult to keep on a heading and resistant to corrections. We have rented a WS Tempest 170 and find it tracks straight but will turn when requested. The Sea Lion is somewhere in between. To date we have been paddling in a bay and along the coast when it is calm.
It goes without saying that we are beginners and probably have technique issues, but we don’t understand why the Cape Horn is both difficult to paddle in a straight line and turn. Is there a set-up issue that we are missing? The comments above are with the rudder out of the water.
Thanks for any advice you can provide.
Steve
How big is the person in the Cape Horn?
Height and weight. If the person paddling a kayak is too small to get it to its waterline, any kayak is going to be harder to handle. It’ll respond more to wind and it won’t be at the best waterline on its hull for turning.
There may be further issues with the basic characteristics of the Cape Horn itself, I don’t know the boat well enough to comment on it. But for starters, best to find out if the paddler and boat area proper match.
Good point about the boat’s load.
I wonder, if it is sufficiently swedeform, if the bow is “pinned” and resistant to turning, while the stern is “loose” and wandering while paddling straight ahead. We have a swedeform canoe that behaved that way, until I moved the load sternward enough to loosen the bow and get the stern more fully engaged.
A too-light load in that kayak might increase the effect of trim, especially if the boat is trimmed a fleck bow heavy.
Prelude to new?
Steve,
You laying the foundations for surprising your wife with a new kayak? Blame the gear! It’s always the gear!
Get her a new spiffy kayak while you keep the Aquaterra. It’ll be an excellent investment! 
If you’re in the area, I can even help you out on the selection.
See you on the water,
Marshall
The River Connection, Inc.
Hyde Park, NY
www.the-river-connection.com
hdusonriverpaddler.org
The paddler isn’t small
But I guess we could try adding weight to the stern. At least it’s free!
I’ve been involved in enough gear driven sports to know that it’s always the gear. No need to improve, just spend money! So yes, i could just buy her a different boat that we know works. I’m just curious why the Cape Horn seems so stubborn.
Sounds impossible
The idea that the boat is "difficult to keep on a heading and resistant to corrections" sound impossible. If you utilize whatever "looseness" in tracking that is present - the same characteristic that makes the boat reluctant to stay on track - it should be easy to change the heading. For example, if the stern is loose, your difficulty in correcting the heading might be due to using a technique that emphasizes sliding the bow sideways rather than the stern. This is pretty much the same in principle to the comments on proper trim mentioned above.
I'm not a kayaker but I think boats are boats. In my experience, if a boat doesn't naturally tend to track strongly it is easy to change the heading. How can a boat naturally wander off its current heading EXCEPT at the moment you want it to?? By the same token, saying a boat tracks strongly AND is easy to turn never actually means that it turns more easily than a boat that tracks loosely, but instead means that the boat turns "easily enough".
Some Guesses Here
I've owned a Cape Horn 15 and the Tempest 170. I weigh about 165 pounds and the 170 was too much boat. I was like a bobber in that thing. The Tempest 165 performs much more nicely. Are you SURE you're in the right boat for your size? 'Fess up now. How much weight are we talking here?
I agree with Guideboatguy... never heard of a boat that wouldn't track OR turn. Maybe the Cape Horn is warped? Does it want to veer one direction?
Not so sure.
I’m not convinced that there is a real boat size to paddler weight ratio that is written in stone, but there is a skill ratio. I’ve paddled a ton of boats of many different sizes and haven’t found one yet that couldn’t be managed, albeit some are more cooperative than others.
Before you analyze a boat’s handling characteristics, it is always instructive to determine for sure if the boat is indeed straight and not encumbered with something out of shape on the hull. In my experience, other than examining the hull very carefully with special interest in the straightness of the keel line, you will need a body of water with absolutely no current and when there is almost zero breeze. If the boat will paddle and glide straight for at least a ways under those conditions at least you will know whether it’s something about the boat. As for turning, different boats absolutely will respond to different techniques in varying degrees, but if the boat will not respond to a forward bow rudder, then you really do have a problem.
More on size
I just ran a quick check on the reviews on this site of people who have liked the Cape Horn 170. All guys, from 5’9" to over 6 ft, weight 165 up to 180 or so.
That is a fairly tall woman. I am guessing that you are trying to be artful about the weight of your wife being centered lower down. But having a lot around the middle does not add inches to anyone’s arm length or torso height.
As to the above comments about the boat neither tracking nor turning - that sounds like either a weight distribution issue or something more fundamental with the hull. One thing that I have found to help tremendously is getting the trim right in my boats. The days that I launch with inadequate caffeine in my system and get it backwards - one boat trims heavy in the stern and the other in the bow - I am not even a mile away before I have realized my mistake.
So you may want to mess with the trim, see if changing your current habits makes it behave better.
Size
So I’m 6’-6" about 190lbs, the wife is 6’-0" 200lbs+. We aren’t small people! She seems more frustrated with the Cape Horn than I. I realize it sounds illogical to say the boat doesn’t track straight but it difficult to correct, but that is the vocabulary I currently possess. We don’t “trim” the kayaks, we get in and paddle! Working on the weight distribution is a good next step. First task sound like it should be moving the seat as far back as possible. Thanks for your help!
You just found out why it’s very
important to paddle a kayak before buying. It’s amazing to paddle a kayak that doesn’t track or respond to paddle strokes. What were they thinking. I find that paddling a kayak that responds well to my strokes is the most rewarding for me to paddle.
Getting the kayak to turn
In order to turn, one end or the other has to be loose enough to make that easy. So one of my sea kayaks trims heavier in the stern because the bow is very tight in in the water - the stern needs some weight to balance that out.
The other boat trims bow heavy because the hull is actually too big for me, in a boat designed to have a loose bow to start with, so usually I want a little more weight to tame the bow. Otherwise I am spending all my time on course correction. There are exceptions, like surf, where I want the bow to be as loose as it can be.
There is also a built-in tendency in most kayaks to weather cock (turn into the wind) rather than lee cock (turn tail to the wind) if given minimal guidance in wind. That is because it is considered safer to weather cock than to lee cock when things get nasty. By weather cocking, you are looking the bad news in the face.
Moving the seat back will shift the trim some, given your sizes. If you need to do more, you can always carry extra water. Just use float bags so it isn't rolling all over the place in there. It makes an annoying noise.
You also need to be attentive to whether one boat simply tends to weathercock more than the other. They are two different manufacturers and not all manufacturers worry equally about weather cocking. I can name some kayak makers who work very hard to design boats with minimal weather cocking, I can name some who have traditionally placed a higher priority on other aspects of a boat's performance. They are all fine boats, just different priorities.
This individuality is more of an issue with older sea kayaks by the way. For better or worse, the major manufacturers are racing each other to get new designs out there with a benign personality that will make all the people happy all the time. It can be argued that the quirkiness of the older designs made for a better rounded paddler. But it also made marketing them more challenging, and even kayak makers have to pay their workers and cover their mortgage.
The Human Factor
It sounds to me like there could also be some stroke dynamics at work here. The human factor can have a huge input on handling characteristics. Are your wife’s strokes symmetrical? Are your strokes symmetrical? Do you both hold your paddle in the proper position? Do you both have a properly sized paddle? Do you both keep the boat relatively level when traveling straight ahead, or do either of you lean the boat excessively on one side only in order to compensate for a hitch in your stroke?
I know that when I’m stern-paddling a canoe I have a better touch when paddling on the starboard side, which is an egotistical way of saying I lack touch on the port side. I’m sure a bit of that asymmetrical touch carries over to my kayak strokes as well, but not enough to bother me. My girlfriend on the other hand struggles on her right side. I spend most of our time on the water together observing and critiquing her stroke. Thankfully, she appreciates this and she improves every week both in technique and strength.
Before you buy a new boat or junk an old one, do some serious observations of each other on technique and trim, and also see if you can get someone with a bit more experience to spend some time observing both of you on the water too. You might find the answer, or part of the answer, is right in the palm of your hand… literally.
A thought
From another newbie.
You or her may not be centered and favoring one side. It took me a while to figure out that I had to “cheek over” a bit one way or the other just a touch with my sea lion to get her as level as I could to get it to track well. The foot pegs have to be adjusted correctly also. Tight enough to get a bent knee and a little pressure, loose enough to be able to get a little stretch if needed.
Hit some real flat water and pick a point across the way, using good form make long EVEN strokes with a pause between each and try to stay on target through the stroke. If you tend right, then you need to cheek right a bit because the kayak is a little deeper to the left and wants to go right.
Could be wrong, but it seemed to work for me.