ok,

I may expose myself as a complete idiot but I have found oil deposits on the plugs (number two anyway, its the only one removed).

I came to the conclusion that the head gasket has gone (bubbles in expansion tank but no milk so hopefully not too bad).

So after stripping off the carbs came the plugs and I noticed a reasonable amount of fresh oil around the thread of the plug but not on the ignition part.

I have a Dynojet kit to go in (the main jet is smaller is this not strange?) and will be doing valve clearances when the head is off.

here are the pics

 

Oil on the threads and outside of the plug means that the valve cover gasket is leaking into the spark plug area. If it were burning oil from the rings, it would not be fresh oil but white and powdery.

 

well i must say that is a little encouraging, the valve cover gasket was ordered as i am doing the valve clearances. I really hope your right

there is no smoke apart from a little when first starting cold so i am hopeful its not worn rings.

 

of course i have assumed its oil and not unburned fuel, could it be fuel ?.

 

The tip of the plug doesn't look all that bad. How many miles are on them?

 

I have only had it two months but if the receipts are to be believed they were change about 5k miles ago.

 

Little rich, maybe....

 

dynojet kit going in so hopefully will sort that out.

Is there a way I can inspect the rings ?. If I can't see something obvious with the valve gasket I would like to be as sure as I can be that I won't be stripping it down again.

thanks for your help btw

 

The only way to check the rings is by doing a compression test and a leak down test.
If its not burning oil, the rings are probably fine. If the smoke on first start is blue-ish, the valve guides may be getting worn a bit and letting a little by when it sits overnight.

 

+1 on the valve cover gasket. Be sure to check the plug boots too to make sure they aren't oil soaked. More then likely they aren't but you will want to check while you have it apart