As a drummer, I will say that riding a motorcycle and playing the drums do seem to require very similar brain patterns. The fact the one person has a sense of rhythm, while another does not, is really immaterial. As drummers, we are taught to develop the skill of "coordinated independence" - that is, the skill of moving one's limbs in an independent, but coordinated, manner controlled of course by the brain. The term was coined by a man named Vic Firth, in his landmark drum method book of the same name. That book was my drumming bible growing up, and I do think it helped me a great deal in learning to ride a motorcycle. I am fortunate that both sets of skills came rather easily to me.
I realize that these skills may not come easily at all to some... but I do believe that the FIRST hurdle to overcome is the very powerful unconscious psychological barrier attitude of "I can't do that". Once one decides that one CAN do something, actually learning to DO it becomes far easier.
My private teacher once told me that famous old showbiz quote: "You know how you get to play at Carnegie Hall? PRACTICE, PRACTICE, PRACTICE!"