Engine rattle and tickover questions

[CMF_Nigel]

Got 2 questions guys,
Engine rattle.
Changed cam chain and tensioner and noise has reduced its less "slappy" and "clattery" now just loud "tappety" but the strange thing is this, on some starts the noise dissapears totally, and remains quiet while ever the engine is running, trouble is a restart can mean the rattle returns. This is all very random with the majority of the time the engine running noisey. I suspect a blocked oilway or somthing.
Was going to try an engine flush and Oil and filter change using slick 50 or somthing, any ideas please?
Idle drop
The engine speed takes about 3 seconds to drop to idle after coming off the throttle. i.e. when stopping, revs drop as foot is taken off throttle but tickover is quite high, after about 3 seconds tickover drops to normal speed, any ideas again?

 

[CMF_Nigel]

any ideas guys, this is driving me mad. Worried about the engine flush incase it knackers some seals but got to try something

 

[CMF_Yom]

Yeh I would suggest changing the oil.

What tensioner and chain did you replace? Both of them?

 

[CMF_Brendon]

maybe its the tapets?

 

[CMF_Yom]

didn't think the cg series had them at all.

 

[CMF_Nigel]

only replaced top chain and tensioner, it was streched so far it was ready to jump. Bottom chain looked too dficult for a monkey like me, but did not have the same slack as the top. Thanks for the replies so far, going to change oil and filter this weekend along with some wynns engine flush. will let you know the results. Was tempted to add Slyck 50 as there is the extra chain mechanism from average engine would it be worth it?

 

[CMF_Yom]

I dunno about the slyck 50. I'm starting to prefer quality oil over additives.

The bottom chain could be making more noise than you would expect too btw.

 

[CMF_Nigel]

just changed oil and filter, it needed doing, but has made no difference. It may well be the bottom chain, but its beyond my capabilities and equipment. So she runs till she dies, I've spent as much as she cost me in the first place trying to fix the noise, a cheap sub woofer would have masked the noise better than my efforts.
Thanks for the replys.