Engine Noise

[Gnasher]

Oil and filter, fuel filter and spark plugs all changed went with iridium and the Westway oil which seems good quality.

I've never heard of them, quick look at their website and they would appear to be just disturbers and rebranders, not refiners i.e. they approach a refiner and repackage one of their range of products, a bit like supermarkets own brand.  Supermakets don't make beans, soup, cornflakes even oil etc, what the do is repackage basic product and sell it cheaper.  Oil is all made to a minimum standard e.g. API, JASO etc.  What well know refiners Shell, Mobile, Fucus etc do is exceed those standards and add better additives.  As long as the oil is made to a API etc it will do what it's supposed to, just.       

Was told when purchased that the guy serviced the bike last year, the state of the oil (bearing in mind the few miles it's done in last 4 years) and rusty spark plugs with grit on the threads  :eek  made me think otherwise.

Rusty plugs and grit in the plug wells is normal, obviously if there very rusty and the electrode is badly worn they've been in a good while.  The electrode condition is far better guide as to the age of a plug than the outside.     

The noise hasn't disappeared but I believe is a lot clearer with the new oil. It doesn't seem to change with the revs or clutch in like most noise complaints appear to. When riding it's barely noticeable, likely due to other noises covering it. It's idle or low speed with clutch pulled to quieten the engine when it comes out. More of a rattle than a tapping now. Doesn't seem to be consistent with the engine timing, like something is loose but can't find anything external but will inspect further.

Carb inbalance and/or incorrect idle jet setting/s will give you very similar noises.   

Assume the cam chain noise would disappear with revs so I'm tempted to rule that out.

If the cam chain is the issue the noise will increase as the revs rise. 

Any ideas?

Wait until you've balanced the carbs and don't forget to reset the air mixture screws.