Hi, all I have the neon green 765 Moto2, fabulous bike! 3600km, service done. One problem - after longer periods of standing unused (a few weeks and more), on startup, the engine runs very dry for a few seconds, like there is no oil on the chain. Sounds horrible,that chain ratlle. When used regularly this does not happen. Seems the oil runs off chain completely? My other bike (1050RS) has never had this problem. I've never had this problem with any of my previous numerous bikes from numerous manufacturers. Is this "normal" for 765? What can be the problem? Cheers, y'all!
As long as it rattles only briefly on startup there is nothing to worry about. The hydraulic cam chain tensioner needs oil pressure which takes a moment to build after the bike has been idle and some oil will have drained away. All engines are different with some noisier than others.
If you park it on a paddock stand then you may find it better. The sidestand being on the left tips the bike away from the camchain tensioner and so aids draining , not ideal in this case, which is probably what is happening.
Hydraulic tensioners also use a ratchet which locks in position and stops the tensioner losing tension completely when the engine isn't running. It might be worth taking the tensioner out and checking to see if the ratchet is working correctly. There are procedures to follow when removing and replacing the tensioner so, if you do decide to inspect it, make sure you follow them as per the workshop manual.
That dry startup rattle after sitting is pretty common on the 765 oil drains from the cam chain tensioner when parked. If it goes away after a few seconds, it’s likely just the tensioner refilling. Not ideal, but normal for these. If it bothers you, a manual tensioner upgrade might help, but most just live with it. Keep an ear on it if it gets worse though.