400/4 engine noise

[Rirons]

I rebuilt the engine last year new bearing etc, on the left hand side ( when sat on it) there is a ticking noise I thought it was tappit clearance so reset them several times without impact has anyone got some suggestions what to look for during these dark winter months. I am thinking a bent valve or worn guide bush ?
Thanks

[mike the bike]

I had the same tappetty noise not long after a rebuild.  After taking the rocker cover off to investigate, it turned out to be the tacho gearing on the camshaft was cracked.  The cam that's in now has worn lobes but it's quieter.   If anyone knows someone who can repair the cracked gear on the cam, please let me know.

[Bryanj]

As slight blow from the exhaust to head gasket sounds just like a loose tappet

[Rirons]

The noise is the at the opposite side to thetacho gear, I work for a gear company and I can't think how to rework the cam with the integral gear

I think it's head off and check the flatness etc, something to do in winter

[Trigger]

Have you removed all the tappets and checked that none are chipped ? Also check oil feed to that side of the head, had a twin in once that had tappet noise on the side stand but, it was fine on the centre stand.

[Rirons]

The head is now off and stripped down, the inlet valve on the noisy side is bent slightly so im thinking that wont help.
next the head is not flat, so needs skimming, anyone know somewhere that does this in west yorkshire?