There was a video on here somewhere about two guys who had been riding/racing dirt for fifty years. One of them has Menieres and although there are days he has to not ride he was just hauling ass on the trails in the vid. Maybe some other inmate here can remember his name but he was damned impressive. It need not be the end.
Google "fifty years of kicks" a documentary on him.
R1150 GSA, KLR650, K75s, RD350, PS250 (Big Ruckus), R65, 990 Spyder
If I still had every dollar I spent on motorbikes I would be a richer man but a poorer person.