Up to 50k there’s no problems. But, above 50k I’m gonna end up emptying my glycogen storage.
(like you, he eats carbs when riding long distances--even with the aim of staying in ketosis)
I eat a lot of carbs ( mostly clean, veges and fruits ) and cook most of my food at home. I’ve been maintaining weight but haven’t really lost much fat.
I know my diet is the reason, so the answer is probably to reduce carbs and increase the proteins. Perhaps try for a longer intermittent fast.