Removing the clutch cover and clutch hub

The next step for me on my way to splitting the case is to remove the clutch cover. This was another stubborn one.

Using an impact driver to remove all of the case screws carefully, I then proceeded to try and remove the advancer per the instructions of the workshop manual. The 13mm bolt would NOT budge at all. After a little soak in PB Blaster, I brought out the breaker bar and got it off without any problems, then proceeded to remove the kickstart lever.

At this point, the only thing holding the cover on was the gasket and without there being any pry points, it was kind of hard to remove. I started by using a thin blade to try and get through some of the gasket material. Then I resorted to tapping on a piece of wood against the case, with a mallet. This broke the seal and after some gentle coercion, I was able to remove the cover.

With the cover removed, the clutch plate, hub, springs and friction plates needed to be removed. This simply involved removing 4 bolts and 2 circlips.

The sprocket and hub came off without incident. I am now that much closer to splitting the case.

Fail Piston

Looks good, doesn't it? The piston has been soaking in penetrating oil for a few days now and I still cannot remove the stuck top piston ring. That and the corrosion on this guy make me realize its time to source a new piston. Fail.

Removing Valves - Part 2

Just received the 'genius' valve spring compressor and was able to get the valves removed on the old head without any issues. The 'new' head I have, the springs seem to be either a lot stronger, or rusted up somewhere. They are soaking in PB Blaster right now before I try to remove them again. Here are a couple of pics of the genius tool in action:

 Here I used duct tape to avoid scratching up the valve

Removing Valves - Part 1

Craftsman valve spring compressor = Good for intake valves. Impossible for exhaust valves.

Good job I have 2 cylinder heads to work with. The craftsman tool is kind of screwing up one of them. Different valve spring compressor now ordered...

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.

The rebuild, as it stands

Here is a brief summary of what is done, what is not done and basically all that has happened since purchase in September 2010.

The bike as purchased:

Strip down in progress:

-Frame stripped and powdercoated satin black

A good number of parts have been bought, including a fuel tank, wheels, carb holders, clubman bars and various other bits and bobs. So far the emphasis has been on disassembly and the replacement of aged/corroded/broken parts.