KZ650 Sleeper Build (KZ1000 engine transplant)

Discovered these RC cams don't have a M6 thread on them like the Yosh 650 cams have in them.





Will need to make up a slip collar for those cam ends to be able to use the degree wheel. Will get it turned on the lathe.

I made up this degree wheel years ago to bench test those Pop Y stage 2 cams because I could not find a timing card for them. I wanted to know the duration so it was a solution to do it off the bike. At that time I did not want to tear into a engine to do it but had did have plenty of spare heads sitting about.

Are you sure that cam timing with the degree wheel on the cam shaft instead on the crank shaft gives you accurat readings?
 

Scirocco wrote:

Are you sure that cam timing with the degree wheel on the cam shaft instead on the crank shaft gives you accurat readings?

 

This was only to find the duration of the cam lobe with no cam card specs available using the bare cylinder head on the bench.

Now that I am retired if I get a few things accomplished during the day it keeps me out of trouble. Got a 50KM bicycle ride done around noon then got out on the lathe and finished the cam end mount to fit the tiny degree wheel on these cams.



I made that adapter out of some UHMW engineering plastic scrap I had in my bin.

Mounted it on the cam then put it on the head, fits better than I though and the wheel just clears the head.

 

 

 

Again this is just to bench test with, it will make it easier to find the duration of unknown cams that I don't have specs on.

I also greased up and installed some valves and a spark plug to check the combustion chamber volume and piston dome volume so I could find out the static compression ratio. I was in a bit of a rush so I never took pics, but I got it done and found out my head is at 38 CC and my piston come is at 12 CC. I input all the variables into a online calculator and the results were 10.45:1 which is just about where I wanted to be for a street engine.

 

Glad I was able to get that put to bed.

I will try to get back on this tomorrow as there is not much going on, I still have some more things to check as far as the head goes. I also need to take two valves back to my engine guy to grind some off the tips.

I found my cam timing equipment but could not find my valve shims.



Moved onto the installed height valve spring (seat) pressure with new APE .440" street springs.





Cycled them all 10 times to coil bind then based lined them at 1.300"



Was able to set intake side at 82 PSI with one .010" valve shim and exhaust side at 86-90 PSI with two .010" shims (copper sheet)
Good thing I did not need thicker shims, will run across them somewhere around here. 

At full lift I can get a .070" feeler in between the coils so lots of room. 

Happy to get that done now I just have to find out how wild these cams are.
 

I was able to use that tiny cam end degree wheel to find total duration on these cams at .050" lift with .006" lash.



Here is the missing timing card based on the actual measurements recorded using the dial indicator and degree wheel.



This was generated thru the WebCam online cam timing calculator.

The cams end up being very similar to the cams I am running on my 831cc street bike, which has a nice lumpy idle.

Found a unusual thing on this cylinder head that I all but forgot about.

The #4 exhaust guide has been replaced with a aftermarket bronze guide that uses a cir clip at the base of the tappet bore. Odd thing about it is the PO had not ground the spring cup to make it sit flat (clip was raised up by .075")

I looked to see if any of the spring cups were modified and they were not, so I needed to grind a "thru" slot with my Dremel tool to clear the cir clip "ears".

First time I have ever done this modification and the first time I have seen a guide like that.

Hard to get a picture of it installed, this is the best I could do. Forgot to take a pic of the ground spring cup.





Only the "ears" are showing as the rest of the clip just fits where the radius on the spring cup is. It is sitting flush on the bottom of that bore instead of rocking on top of the clip like the PO had it. The ears are still .035" proud of the spring cup but the spring ID is bigger so there will be no interference.

Got all the valve spring shims installed under the spring cups and the valve seals installed on the guides. All ready to fully assemble the valves and springs the next time I am out there.