They&#x27;re easier to activate because they&#x27;re self-energizing (I&#x27;m sure Wikipedia has a handy diagram that explains). But drums don&#x27;t stop as well (not an issue when you&#x27;re on crappy bias-ply tires), and they tend to fade under repeated braking. They also loss stopping power in the rain more than discs do. Not as important, but I&#x27;ve found disc brakes to be easier to modulate as well.<p>There&#x27;s no power assist on most motorcycle brakes. I&#x27;ve owned motorcycles with drum brakes. OMG, I&#x27;ll take the disc brakes any day, power assist or no.