+1 to a non serious coolant leak guess. Last winter, my '04 GSXR 1000 had a small pool of antifreeze under the bike. I followed the leak and it was coming from a hose clamp. I ran the bike in the spring and during warm up the bike leaked a bit more before sealing itself again. The rest of the season there was no more leak, and even over this winter it's stayed sealed. I thought I'd be ordering a new hose and clamp, but haven't had to yet.
check the clamp by the rad cap and thermostat. I had a z1000 in a while ago.....that had a leak around the hose.
Found the old pictures...it was leaking by this fitting (yours does not look like its leaking here) and the hose clamp, check the bottom of this fitting...its the temp sensor for the fan trigger I believe...
The bike in the pics had less than 20K on it.
You can also see the ground to the housing, where you are missing a bolt. It should be a M6x1.00...
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