It isn't, in motorsports as you said it has to do with the specs of the motorbikes, it is similar to weight classes. But delineating sports the way you propose would be really stupid because you're not delineating via a specific well defined feature but via outcome which doesn't make any sense in terms of sports. It would pretty much just become "who can consistently run the course in exactly 1 minutes and 50 seconds".
It isn't, in motorsports as you said it has to do with the specs of the motorbikes, it is similar to weight classes. But delineating sports the way you propose would be really stupid because you're not delineating via a specific well defined feature but via outcome which doesn't make any sense in terms of sports. It would pretty much just become "who can consistently run the course in exactly 1 minutes and 50 seconds".