engine noise--normal?

[platinum350]

Hey,
When I start my stock 400ex when it is cold I hear 2 noises that I am unsure about. The first noise sounds like I can actually hear the piston sliding up and down, kinda like a hiss. I don't really remember if it goes away once it's warmed up.
The second sounds like a clicking noise in the motor. Maybe the valves?? I thin that one goes away shortly after it is warmed up.
Keep in mind I am new to owning a 4 stroke, all I really know is 2 strokes.
Thanks for any help!!

[mojoe2878]

clicking is probably the piston noise, and if it goes away after it warms up then its normal. it will do this until the piston warms and expands to make a tighter fit in the cylinder.
the hissing noise is probably the cam chain and wont go away after warm up, its normal too, the cam chain is constantly rubbing on guides and will make a noise.

[platinum350]

cool, thanks!

[chad400ex]

More likely is that the clicking noise when your bike is cold is your cam chain slapping around. I had a similar problem a couple years ago. All I had to do was up the idle speed just a little bit to keep the motor from idling roughly when the motor was cold. As soon as I upped the idle speed, the slapping/clicking noise went away.