Manifold or tappets?

[izthewiz]

My Chimp has had the precats removed according to the previous owner, and I've read somewhere that some side effects of this are noises that mimic those of tappets or a cracked/leaking manifold, which I can hear, but not identify.

Is there an easy/cheap way to ascertain the exact source of the noise?

I await the bestowal of the collective PH wisdom....

[Belle427]

I would say it does not mimic them to be honest but manifold gaskets are very common to fail.
A pita to do but maybe something to think about if just as a maintenance job.
Tricky to pin down, the old tissue paper trick may help holding it in various places to see if it blows around.

[TarquinMX5]

I can't say that I've heard that 'mimic' view before. Presumably no obvious marks on the manifold to indicate leaking exhaust gas?

[izthewiz]

I've got a sinking feeling that it's going to be the tappets. Manifolds seem pretty leak-free as far as I can tell, at welds and joints.

Any other suggestions as to what it could be, or how to check?

If it is tappets, what are my options?

Thanks.

Iz

[Belle427]

May be worth pulling the rocker covers just to check the pads are all still on the rocker tips.
What grade of oil do you use and when was it changed last?