Swapped: coil Box ballast. Problem still exists. Readjusted the carb and gave it 18 deg advance at idle. Marginally better. See video what happends when i stop after cruise. It was not thet hot and engine was struggling to run and it ran but you can hear and see the problem. My friend says it can be aluminium intake ( dp4b) and low rpm plus very hot fuel resulting in fuel boilingninnintake not carb. https://youtu.be/4h_DuQsF_Vk