As the previous wheels were too heavy and unstable I decided to make my own frame by turning wood and using the axle of the pram. I cut the joints at an angle so the boards, that the kayak hull will rest upon, sit even. I then fastened another piece of wood to strengthen the 2 legs. I up-turned the kayak positioned the frame and bunji strapped it onto the hull.
After some adjustment I tied it to the bike and positioned the frame in the centre of the kayak, it sat balanced without much weight on the bike frame. I gave it a test run for about 1 mile and it ran very well, it bounced less than before and felt sturdy.Turned easily and did not pull to much going up hill.
I will do a test run to the sea soon and if that is successful I will design another Crab-Claw rig for the kayak.