Another warning: Do not leave open pans of coolant sitting out. Dogs and cats are attracted to the sweet smell of coolant, and will drink it given the opportunity. This will KILL them in a horrible manner - coolant is poisonous! Avoid expensive vet bills and unneeded strife, and bottle up your coolant as soon as it has cooled.
1. Remove the false tank. You can find instructions on how to do this here. Put your pan underneath the front of the motorcycle, directly behind the front wheel, and undo the coolant drain bolt, directly beneath the thermostat housing, and next to the oil drain bolt.
2. The coolant will start dribbling out. Make sure your pan is right up as far as the front wheel, because the next step will have coolant gushing out.
3. On the top of the bike, directly in front of the coolant reservoir, you will see the radiator cap.
4. Remove the radiator cap. The coolant will start gushing out into your pan.
5. Using pliers, squeeze the retainers on the reservoir hoses to loosen them, and pull them back. Then remove the hoses from the reservoir.
6. Remove the bolt holding the reservoir to the frame of the motorcycle.
7. Loosen the reservoir cap slightly, and pull the reservoir back to remove it. Open the cap and drain the reservoir into your pan. Clean the exterior of the reservoir.
8. Replace and snug the coolant drain bolt.
9. You will need two one-gallon jugs of distilled water (it must be distilled only).
10. Using a funnel, pour the water into the radiator until it reaches the neck of the filler.
11. Start the motorcycle and let it run for three to four minutes. Carefully monitor the filler neck and add water as required to keep the water level near the top. Stop the motorcycle, and remove the coolant drain bolt. Allow the water to drain from the motorcycle, the replace and snug the coolant drain bolt.
12. Allow the motorcycle to cool until the engine is warm to the touch. We don't want to pour cold water or coolant into a hot engine. Repeat steps 10 and 11 again with another gallon of distilled water.
13. After draining the water from the engine the second time and snugging the coolant drain bolt, allow the motorcycle to cool until the engine is warm to the touch once more, then fill the radiator with coolant. This is where I prefer to use genuine Honda coolant, to preserve the delicate seals on my water pump:
However, any modern pre-mix coolant usable on aluminum engines is acceptable, but it absolutely MUST be "silicate free."
This Prestone 50/50 premix should also work well:
14. Note that the coolant must be "Silicate Free" as shown here. Coolant containing silicates will destroy the seals in your water pump in short order.
15. Run the engine for several minutes, adding coolant to keep the coolant level near the top of the filler neck as it runs. You may need to rev the engine several times in order to get all the air out of the system. Each time the coolant level drops, add more coolant to bring it back up to the filler neck.
16. Stop the engine and replace the radiator cap.
17. Replace the coolant reservoir and fasten it to the frame.
18. Reconnect both hoses to the coolant reservoir. Fill the coolant reservoir with coolant to the "Full" line.
19. Start and run the engine until the cooling fan has cycled on at least twice. Monitor the coolant level in the reservoir over the next few trips you make on your motorcycle and add more as required.
20. Replace the false tank.
