In NSW, Motorcycle mechanics do the same TAFE course as car mechanics in first year, but then move to bike specific study in the second and third year. I assume it would be much the same elsewhere. If he is a good car mechanic, it shouldnt be to difficult for him to switch to bikes. I dont know any bike mechanics (or apprentices who are old enough) that dont have a bike licence. Road testing for faults, and to confirm a satisfactory fix, is an important part of the job.
Laurie