Well that seems o.k. then.Matchymarty wrote: My previous piston was a Wellworthy, and currently using a JP Piston (Aust) rings. Top two rings do not have an up or down, ie. no rebates or chisel shape to ring. Oil ring is 'solid' as in 1 piece ring, with slots cut in it, and also does not have an up direction to my knowledge. In anycase, my engineer gaps the rings and installs them on the piston for me, as he know's the rings and pistons well, and that way I don't stuff up which way they go on. Current 'new piston' is a JP +0.060" and has been ceramic coated.
Too much oil getting into the combustion chamber (as we are already well aware) combined with a (not unusual) poor seal at the plug washer.As for the oil coming from the spark plug hole, the oil seems to seep past the plug during running. Now, the first 18-20 miles, this did not seem to happen. Only on returning after 30 miles had been done, and the bike stopped and wouldn't restart, did I notice the oil on top of the head and surrounding the plug.
I would think that the long hose was fitted either by the previous owner or yourself, especially in an attempt to cure this topic's chronic and ongoing oil/smoke problem when it first arose, Is the 'long hose' still fitted? Since the breather points downwards a hose would normally have be routed upwards to its open/ discharge end. This means that instead of a fine oil mist constantly drifting down onto the road via the standard approx 3" long breather tube a dollop of coagulated oil will collect in the lower run/loop of the hose causing back pressure and inhibiting the free movement of the breather disc. In addition, if the oil puddle/dollop in the long hose is causing back pressure or even blocking the hose the crankcase pressure will increase forcing oil up the bore to get burned, make smoke etc.As for the crank case breather, it always seemed to push oil out of the long hose I had finishing near front of back wheel. Always made a mess. Does this mean too much oil in the sump?
Perhaps you haven't re- fitted the long hose so I won't waffle on about the possible effects of it any more
The main issue seems to be one of a smoky zorst and the plug oiling up, whether that's from oil coming down into the combustion chamber from above, or being forced up from the c/case. However, the consensus seems to be that it's oil being forced up from the c/case and also out of the c/case breather. Since these symptoms don't occur in the first 10 miles or so after start up it's unlikely to be a case of wet sumping. Therefore I suggest that you a) drain the crankcase and then go out for a run until the smoking starts (take a spare plug with you!), return home and drain the c/case to measure how much oil has collected. Then just for the sake of eliminating the wet sumping possibility replace the drain plug and leave the bike a minimum of 24hrs and drain the c/case again.