Rattling on first takeoff

[4bye4]

Sounds like the engine bay. Doesn't rev in neutral only in first I can't actually remember if it does it in reverse too or not. It's like a clacking and rattling noise. But as I said before it goes away after taking off.
Manual trans

Ok if its engine it may just be the injector pump. not knowing the sound and how loud it is makes it a bit hard to guess though. It could also be the rockers not getting enough oil maybe. I doubt its the gearbox oil level, but hard to know without hearing it. If it bothers you or gets worse, take it to a mechanic for and opinion, otherwise turn the radio up and shut your eyes. Seriously though, its a bit hard without hearing it and may be nothing or a portent of somthing disarsterous.