Noisey top end on early CB550F1

[Yoshi823]

I once owned an early 550F1 & it came to me with a very rattly top end. I tried resetting the tappet clearances but no joy. Even after changing the oil it didn't quieten down at all. So I had the rocker cover off & started to dismantle this part.
http://www.cmsnl.com/honda-cb550f1-super-sport-550-four-1976-england_model17113/partslist/E03.html

What I found was that on the early 550F1s there are individual rocker shafts for each rocker.

Having procurred a later 550F2 or K3 rocker cover...
http://www.cmsnl.com/honda-cb550f2-super-sport-550-four-1977-england_model17121/partslist/E04.html

...this cured the irritating noises & the engine then ran as sweet as...