I have built a kayak erg from a nordic track. It was the super-fancy health club version with two flywheels and full electronics. Mine does not have an integral balance stool.

The model NT I used has a much larger flywheel than the one he used. I originally set up my ropes like his, which is an imitation of the Speedstroke Gym by Kayak Pro. I found that the rope stretched and wouldn't put enough tension on the rollers to get the flywheel moving, and if you did get it moving without jumping the rope off from the front guide pulleys, you couldn't (obviously) put more tension on the flywheel to vary the resistance. My ropes now go directly to the roller on the flywheel, cross over to the other side, and go back to the shaft. I don't have photos on this computer, but I'll try to post some later.

It is fine. It is adequate. If I had the cash I'd by a Speedstroke Gym. But I don't, so this is better than nothing.

Of note, however, is that Maligiaq Padilla made one without a flywheel, just bungees in the front and in the back. With this one you have to push with the top hand and pull with the bottom. He felt that this was less expensive and better. I made one like that first, but it is very difficult to get the tension on the bungees right, and it feels very unnatural. I could see the benefit for building muscle, though. I got the NT for free and built my current version.

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