Using a coolant recovery bottle ensures that the radiator is all ways full of coolant. If you start running low on coolant when the bike is cool you can just add a little to the recovery bottle and it will cycle into the radiator after the next high heat cycle. Coolant recovery bottles should be placed as high as practicable reference the overpressure port on the radiator, even above that port if feasible. Doing so facilitates the syphon back into the radiator when it cools.
My coolant recovery system is a 4-6 oz plastic bottle zip tied inside the headlight enclosure. The clear vinyl tubing is clamped to the over-pressure port on the radiator then the other end is cut at an angle and inserted into the bottle so that the long end of the bevel sits on the bottom. The smaller tube is the vent for the recovery bottle, it terminates just under the lid so the amount of coolant vented out of it is minimized. Both tubes are a snug fit through holes in the bottle top.
It seems to work as expected as I've seen the bottle more than half full when I was working the bike hard at low speed, and almost empty after the ride when the bike cools.
The middle photo shows the tubing as it loops from the radiator to the recovery bottle. Since is is a clear plastic it acts as a visual indicator of when the radiator is puking coolant. That's a lot neater than a cloud of steam.
>>> see my DIY radiator fans HERE.