Speed cameras can measure
Speed cameras can measure speed in two ways. most of them use a doppler shift radar that calculates your speed by the change in frequency of the waves. Cars reflect a lot of radar, being big and made of metal and glass. bike riders, being small and made mostly of clothes, will reflect much less, i doubt you’d get a reading although i have heard stories of police at mobile speed traps calling out speed readings to passing cyclists 🙂
The other system uses piezo electric strips under the white lines on the road. again, the difference in weight between a bike and a car would suggest that you’re not going to set that off either…