Short answer: Yes. It’s easier to go straight while paddling as hard as you like, and since 2014 all Gumotex come with them, as do many others. Some can be mounted or removed by hand even from an inflated boat, and it’s easy to glue a kit to any IK (left and right).
A few years ago Gumotex IKs came with a horrible optional bolt-on alloy skeg (right) that was way too big and bent easily. After testing a smaller home-made version (left), I got some stronger low-profile alloy skegs made (behind the black one, right) and even sold a few to fellow Gumboaters. Then Gumotex introduced a skeg near identical in shape, but in tough plastic and with clever tool-less mounting (right). I’ve fitted these plastic skegs to older Gumotex IKs and other IKs. The kit (right) is under £20 + glue, and the skeg is very tough. Just make sure you glue it on really well; it helps if your boat is made from a matching rubber fabric.
If you’re an experienced paddler you’ll have acquired the knack of going straight without a skeg – handy for paddling shallow rivers where the skeg would drag. A little more paddling finesse and occasional correction is required, especially if powering on – for that a skeg is definitely better. I fitted the tough Gumotex skeg to my Grabner Amigo IK (right) and at sea used it all the time. But on the shallow Spey (left) that boat didn’t handle well without a skeg, possibly a tailwind pushed the back around. It was really quite annoying as a few years earlier my broadly similar Sunny managed the Spey fine, so it clearly varies from boat to boat.
It’s good to learn the technique of going straight without a skeg. Fix your eyes on a tree or marker on a distant bank and paddle as gently as you like towards it, not looking away and keeping the nose of the boat in line with the marker. By using very light strokes you’ll see it can be done if it’s not too windy when again, a skeg helps with tracking (going straight).
I even found I could paddle a ten-foot Solar without a skeg. Once you know you can go straight without a skeg, it’s just a matter of adopting the same finesse but with a bit more power. Only when you attempt the speeds of a Maori war party will the deflection get too much because you can paddle faster and still go straight with a skeg. Out at sea or on busier rivers, I always use a skeg.
I’ve often thought a hinged retractable skeg with a spring or just weight could be a good idea: it would pivot backwards when dragging in shallows, then drop back down when there’s enough depth. Seems SUPs also have this problem and in the US, FrogFish have made such a thing for boards, but they say the spring can be a weak point. I’ve envisaged something more normal skeg size as I can imagine in rapids drifting sideways into a rock or something might put quite a lot of leverage on such a long skeg. SUPs don’t normally do rapids.
Especially if your kayak has a rudder mount, I think it would be quite easy to make one, if you think it’s worthwhile.
On a packraft the consensus seems to be skegs make little difference. I can believe it before I knew it and now I know it. The bow still yaws or bobs a little left to right as you paddle; less so with a load mounted on the bow. Tracking – actually going straight – is not the same thing and not a problem on a packraft because you can’t go that fast. You move along with a moderate left-right bow shuffle which it’s true, does limit your speed – but speed is limited by a packraft’s hull shape anyway. Or is it?
If anything a packraft skeg fitted under the bow rather than the stern might limit this yawing, but I imagine you’ll destroy the instant turning ability for little actual benefit. Good for crossing a long lake in a hurry maybe. Can’t say I’ve seen this idea mentioned, though I am sure someone’s considered it. Since 2011 we have the more pointy Alpackas where the extended stern has the same effect as a skeg. The idea has been widely copied by other manufacturers and it definitely works.