Over the course of the last 6000km on my FZ8 motorcycle I have noticed a small coolant level drop. I estimated the volume has dropped about 100cc. My motorcycle engine has reached 18.000km approximately. (From an almost MAX level on my overflow reservoir I needed to add about 100cc to reach it again so now I can be more specific next time I check it.) Also there are no coolant leaks visible on tubes, around the engine surfaces into the oil discoloring it or any drips on the motorcycle parking spot
I have also checked this How does the coolant disappear?
So if I was not mistaken and the motorcycle actually consumed 100cc of coolant over the course of these 6000km, would this be normal, tolerable or should I be alarmed?
Is there a way to check for coolant leaks through the combustion chamber in such small amounts?
Is this kind of "consumption" accepted for sports motorcycles in general?