Hi all, thanks for your answers, but i guess it's not that.
after leaving the bike outside for 3 days without starting it (temp ~10 deg C) i started it on Friday last week and i had to stop it immediatelly because of a very loud metallic knock coming from the engine. Left it for 1 minute, started it again and the same thing. The 3rd time started ok without any sound... The 4th time it did the knocking again and i decided to let it run, after 5 secs it dissapeared and was ok afterwards. Took it in the same day to Ducati and left it there for a brake check up and cylinder balancing. They started it this morning (after 4 days not started; kept inside temp 17 deg C) and the same loud knocking sound as last week appeared.
I wasn't there but the guys called me to listen for it. The 3rd time they started it the sound dissapeared after a 5-10secs they warmed it up did the cylinder balancing and waited for me to come to listen it. Of course when i came to the service there was no knocking...
What can it be?
Their initial assumption is that it's a piston bolt and the piston is knocking the cylinder head or the valves.... but they didn't crack it open yet
Help!
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