It seems to me that building a retractable system to bolt to the beams would not be all that difficult. They could include a linkage to turn them sideways as they are pulled up. The design in my head suffers greatly though when such a wide tire is required. It seems it would have to weigh at least 50lbs.
My greatest problem is: where do I leave the wheels during sailing. They ought to be onboard for my purpose, but sailing at sea and in a break with these big things sideways extended is impossible.
The only place seems to be flat, in front upon the tramp, but then I have to have a mechanism that not only retracts them but also turns them 90 degrees.
