Motorcycles can't be caught by Radar.. myth?

Since the biking season is starting to open up, I noticed riders ripping at crazy speeds, like well over 180 200 and way faster a few times, not slowi down for the cameras as well. I'm not dissing them or anything, just curious about the cameras here.

One of these bikers told me speed cameras in dxb can't catch clear pictures of bikes at high speeds, and since the license plate is only at the back and not the front that helps too.

Can anyone verify how true or believable is this? Any first hand experience?