Entrance by Bikes into the Cycle Reservoir
This may sound strange, but in the main bikes are governed by the same rules as cars when it comes to cycle reservoirs. Cyclists can only technically enter the reservoir if there is a feeder bike lane, with a dotted line, which filters into the reservoir. If there isn't a feeder lane, and just a solid stop line that the cars are stopped at, as a cyclist you are supposed to stop there to.
Of course, common sense dictates that this is a frankly ridiculous situation, as it negates any purpose assigned to the advanced stop line and cycle reservoir. General usage, and logic, therefore means that it's unlikely anyone will ever be fined or given a talking to for riding into a cycle reservoir without a feeder lane.