Removing the Cylinder Block

 The KZ400 B1 has 4 pry points for removing the block, 2 on the left and 2 on the right. These served only to annoy me and worry me, as prying on these did nothing. Its easy to deform/break the soft aluminum when the block is stuck tight like mine was. In future, I will ignore the pry points until I have done everything else.

So, the next step was to squirt penetrating oil (PB Blaster) down the stud holes, since word on the street is that a lot of crap (dirt, rust) can accumulate in here and make removing the cylinder block painful.

With everything lubed up and soaking for a day or two, I would attack the block with a rubber mallet. Hitting on the front, where the chain tensioner rod screws in (it being removed at this point) at the back, on the sides at the top. Basically, you want to be gently tapping everywhere except for the engine fins, as I found after breaking off a couple.

The hammering and the lubing gave way to attempts to pry with pieces of 2x4 wood. I was all ove the above for about a week solid with next to no results. Lube, hammer, lube, pry, hammer, lube.

One member at the kz400.com forums advised stuffing some balled up rags down the cylinders (pistons at their lowest point), then bolting the head back on (not too tightly) then turning over the engine with a wrench. I did this until I could no longer move the wrench, so the rags were fully compressed in the cylinder. This did not seem to have done anything, but after I removed the head, I pryed on the left side and sure enough heard the tearing of gasket paper.

So in short: stuff balled up rags down the cylinder, put the head back on and manually turn until you can no longer turn anymore. Remove the head and try the pry points again. Rinse and repeat if necessary.