Cyl head valves

[Megawatts]

Anybobdy no why this looks like it does?
Firstly the pictures are taken with my camera mounted on a borosccope inserted through the spark plug hole so apologies if its not as clear as I would like.
Its the inlet valves, both left and right hand cylinders are the same (build up of oily tar like substance around the back of the valve head), the odd thing is its only on the upper inlet valve on both cylinders, the lower inlet valve is as clean as a whistle on both cylinders. Everything else, exh valves, piston and liner look fine.
Spark plugs look to have right colour to them, fueling seems fine. and air intake clean.
Leaking valve stem seals on both cylinders on the same upper inlet valve maybe??

Ill have to find another GS to internally inspect to convince myself 'they all do that sir'

 

[Rollin Bone]

This is the reason I dont visit this site often..

You Need to get a Hobbie RB

 

[NAB]

FFS

What problems were you experiencing to take photos of your valves, or was it a clear case of "cuss i can" syndrome

 

[T900]

have you checked the clearances yet

 

[DrFarkoff]

Have ya checked the upper stick coil is firing ?

 

[Giles]

Have yer checked yer pulse?

 

[jpooch00]

That's normal, they all do that.

It's common to get buildup on the back of intake valves on most engines. It's due to the fact that the intakes are subjected to a partial vacuum while they're open and oil is pulled down the stem and collects and cooks onto the backs of the valves.

All normally aspirated engines do this and it's nothing to worry about. It's normal. Additives such as Sea Foam added to the gas will remove some of the buildup over time.

 

[bumpmuncher]

dont fix it till its broke and stop riding like a wuss next time you feel you need to fiddle go for a ride. or if you would rather fiddle than ride get yerself an airhead project