I havent seen one tore down to look at it and I hope if I do get to see one its not mine
The head gasket is crushed inbetween the head and cylinder so that is what holds the cylinder in place from the torque that is applied to the cylinder head studs, maybe the cylinder started to move and the head gasket gives up, there is a lot of things that could lead to this. One my be the studs were not torqued correct to start with or the material and size are not adequate for the job they need to do ect. It looks like to me that Harley would have there top motor techs all over this problem or they may see a design flaw and are hoping that enough of them wont surface to have to make a major recall. Is it a problem in a specific serial number range or can it be traced back to rider habits or style of riding. I have my feelings on what it is, that is why I changed mine the second I got it to my shop, metal grows with heat.
At first the response from HD Tech Services was "a bad batch of cylinders" but there seemd to be more stories about bad cylinders than one batch would make.
On the other hand, when mine was starting to leak again after getting the -07A gaskets, my dealer was going to do cylinders, rings and gaskets because replacing just the gaskets seemed stupid. It is possible that a lot of good cylinders were replaced in an attempt to try something different.
Some have had definite liner slippage, but I don't think we'll know how many good cylinders were replaced "just because". I'm hoping as we get more motors running with the -07B gasket, we'll see a dramatic drop in repeat performances of leaking gaskets.
