You should run your coolant at a ratio of 50% water and 50% coolant. The manual for my '99 says to use "soft" water. As for the coolant, buy a reputable brand and you'll be ok. As for how much your radiator takes I don't know. If you called a dealer they will tell you. Or you could fill with water and then empty it into a container and that will show you how much it holds. Fill the radiator all the way and make sure there is some in the over-flow bottle above the "low" mark. Run it for a couple seconds to distribute and then top it off. As for the fuel mixture I believe the factory suggests 32/1, gas/mix. Most guys on this site use different mix ratios that they prefer. I run 40/1 ratio. Again it is a question that your dealer will answer. The difference in the mix ratio is a preference to curb the spooge problem that KDX's are known for and some performance gain. I am by no means an expert on that but it works for me. Good luck.