Outside temperature can be an issue at startup, but not at full operating temperature, since engine/oil should always be at about the same temperature. And that's when the 'ticking' (or clacking?) takes place. But yes, if it was a bearing issue, it'd be getting progressively worse. Remember to do the 'bearing test' of slowly revving engine from idle to about 1,500 rpm and back a few times. If you don't hear the dreaded 'clanking', all is well at the bottom end. It might be a normal valvetrain noise we all have to get used to
. Good day gang.