Get water wetter to fill it with and get about 2-3 gallons of distilled water to flush the system. Drain all the original antifreeze, run some of the distilled water through and try and get the excess out. Replace drain bolt, fill with distilled water, replace radiator cap, run the bike till the fan kicks at least once or twice, let bike cool, remove drain bolt and drain. Repeat this process until you are no longer getting green coolant draining out. Once this is done then you can use the water wetter/water mixture. Make sure to bleed/blip the air out of the system when you are putting this in. I do this by installing it and keeping the radiator cap off, start the bike and as the bike is warming up toward about 150 degrees you can blip the throttle and also squeeze on the radiator hose to try and get the air out of the system. I replace the radiator cap around 150 before it gets too hot to handle.