im leaking coolant... 600rr?

If you are doing a lot of traffic driving, chances are that your bike is running hot and just pushing the coolant out of the overflow. Just keep an eye on it and make sure you keep it above the minimum line. I've had this happen to me in the past because of overheating. Not a blown head gasket, just doing the job it was designed to do. You can also replace the coolant with another product like "Redline" coolant and that could help cool the engine quicker and easier. I use Redline in my race bikes and they cool my engine at least another 10 degrees lower.

You have to pressure test the cooling system to determine if & where there are any leaks.

The reserve tank doesn't have an overflow valve.

Leaking water pump seal - worn relief valve, or non sealing radiator cap - blown head gasket - air pockets are being filled, in the cooling system - cracked and leaking radiator hose.

The problem (if there is one) could be any number of things.

Any automotive or motorcycle shop should have a cooling system pressure tester.

yeah, that isn't very helpful, you don't have coolant in your oil do you?

I've got the same problem, I had to remove all the coolant from my system to go to the track, filled it up to max and now I can't even see any in the reserve. I think it has something to do with the system self bleeding, pushing out air to make room for more coolant, I wouldn't worry about it too much, just keep filling the thing till it stops emptying.

Thats what I did with my mercedez and it doesn't drain any more.

with that many many miles on a bike, you might have a blown head gasket, but you say the coolant is leaking, so there might be a broken check valve. Worst case scenario, the block is cracked and coolant is leaking into the crankcase. If there is power loss, you might have to replace the piston rings. You need to check your oil for any coolant leakage, and if there is then you need a whole new motor. Check your spark plug and look for if it has been lighting the coolant, if so, you would need a head gasket

I'd look into changing the valve, they can go bad just like that. Or if you can look around where the valve is and see if there is a crack or anything like that. Also the thermostat might be stuck open as well and using the extra water.

I think it's th valve - perhaps you could get a manual and look it up.