The nearest bridge to me is the Dartford Crossing. Originally just a double tunnel under the Thames and then they built a bridge as the tunnels couldn't cope with the traffic.
About three years ago they dropped charges for motorcycles. There was another concerted action by local riders to hold up traffic, the police did get a bit lairy but in the end, charges were dropped.
To get through the tolls now you are expected to queue up with the other vehicles and then the barrier is raised and you can proceed. Not ideal. There is plenty of room to have opened a lane or two that were big enough for bikes, even fat arses like 'Wings, and save us queueing. But that is way beyond the comprehension of the private company that the Government sold out to.