KZ650 cafe-racer

However, the complete big bore high compression piston kit (K700) in combination with cylinders painted in black look not just fancy, but absolutely awesome.

 

 

 

Putting  rings on pistons and installing pistons themselves are routine works. However some skills and accuracy are (as always)  of essence.

 

 

With pistons in place and rings gaps aligned according to Wiseco recommendations it was time to prepare things for cylinder installation. First came brand new (Liska Racing) lower idler roller, new genuine roller shaft and damper rubbers.

Then I put in place oil restrictors with new O-rings (genuine again, one couldn’t trust aftermarket rubbers when it came to the oil distribution system).

 

New genuine gasket finished setup.

 

 

 

After this it was time for some special tools again. For cylinders installation Factory Service Manual proposes to use two special tools: Piston Ring Compressor and Piston Bases. Both tools came in one set of tools (under part number 57001-531). Well, all is clear with the piston ring compressor: it allows you to slip pistons into bores without working on each and every compression ring. However, I suppose not everyone has a piston bases in the workshop. They are merely two U-shaped rods that have to be inserted under the pistons to hold them level while you put cylinders on pistons. However, they turned out to be mighty useful, especially in cases like mine, when the secondary shaft and clutch aren’t installed and therefore the crankshaft is disconnected from the gearbox.  Without these components it’s hard to fix the crankshaft in the chosen position and therefore hard to work out the rings. But even with the clutch components and secondary shaft in place, when the position of the crankshaft may be more or less fixed by switching to one of gears it’s more secure to use piston bases when installing  cylinders…

Therefore, I decided to make it all by the book and produced myself another set of special tools. It was very simple with piston ring compressor as I had this ideal in my mind for a long time: I cut off skirts from four carburetor cleaner caps, just like these:


 

And took four wide reusable plastic ties (I use them to mount wiring to frame etc, works much better than ordinary wire ties).

 

As for the piston bases, I was lucky to find two pieces of stainless steel pipe of acceptable diameter. They were bent a couple of times before and therefore far from straight, so I straightened them as well as it was possible and made U-bends of acceptable dimensions.  Not the best of special tools I made, but pretty decent for 15 minutes effort.

 

Complete set of improvised special tools looked like this:

 

And here is how they work. Initially I made bands for rings too wide, so later I narrowed them so cylinders went down further and covered oil rings with bands installed.

 

 

With piston bases and piston ring compressors it was a matter of minutes to get cylinders installed. I spent more time on photo shooting than on installation itself. 

 



I oiled bores because I could not exactly foresee how long the engine will sit on my table before it starts for the first time. 

 

Engine with cylinders installed looked inspiring. 



I installed new genuine dowel pins, O-rings and the latest version of oil restrictors (early KZ650 wasn’t equipped with them, but I picked KZ650 cylinders that for sure were compatible with restrictors). 

 

Next went components for the timing chain’ tension system. I oiled them and assembled… 

 



… then I installed them in place along with new rubber dampers (shafts and rubbers are all OEM or genuine, whatever is the best word for original parts). As the last “brushstroke” before cylinder head could be put in place was installation of a new genuine cylinder head gasket. 

 

With preparations completed it was time to take from the bags all new (and again, genuine) cylinder head nuts and washers: 



As well as cylinder head bolts along with custom made adapters: 



And since the KZ750 cylinder head itself was already assembled… 

And again, it was a matter of minutes to install the cylinder head and torque all nuts and bolts  according to specs. Kawasaki books don’t state using oil on threads and flanges and threads of cylinder head nuts. However, I have read service manuals of different manufacturers and I always apply a smear of oil on both thread and flange of cylinder head nut. A little oil allows for tightening cylinder head nuts more evenly.

 

 



With the cylinder head installed, the engine looked mostly assembled, but still there was a lot of work to do, so the story is still far from being finished.