Strange sound when cold

I hope I can explain this well enough.

I have a CCC can does anyone else notice that when cold starting there is a noticeable sort of hard to describe tapping sound.

I know it's not valve tappets but it seems irregular and sort of every other second or so, so not every rpm but it's an audible sound sort of like if you lightly tapped a spanner on the front of the down pipe and hear it through the can.

I'm not really concerned just curious as it was immediately after I put the can on and very well may be an acoustic sound from engine noises from the new can but once it's warm the sound is completely gone.

[Taipan]

Sticky cam chain tensioner?

my thou makes all sorts of strange noises, much more mechanical than the 650 but hey engines these days are strong i wouldn't worry too much.

I get so many rattles on my 650 i wouldn't know where to start describing them. They are inherently tractor engines

[Wideboy]

i get the same thing on my SV, my sr125 does it as well but i have had no problems

its a feature learn to love it