Hey guys I recently bought a yz400f and dont much about these bikes. I noticed when it's idling, it seems to me that a lot of coolant comes out of the overflow. Once started it's only a matter of seconds and coolant starts coming out of the overflow. Do these bikes warm up that quickly. After an hour of so of riding i needed to put in 1/2 litre of coolant or a fraction less than 1/2 L. Is this normal with these bikes, it does not seem to leaking anywhere else. . The second thing is my bike starts with no choke when its cold. I have never heard of this and researched some of the sticky forums. It may be too large a pilot valve, but i have not pulled the carb apart to check it yet. It runs fine for a while and then idles inconsistently (high, then low and stalls). I put in a new plug and it runs fine again, but when i check out the plug does not appeared to be fouled, it is a little sooty but not wet.