Adjustable cams In a J head

How the hell do I degree the cams with out an old cut up valve cover. How far off will it be and if you tell me i can set it off that much before :ohmy: This would be in a kz1000r2

The rubbing block will add about 2 degrees to the mix. When you install the cover it will advance the intake and retard the exhaust cam. [tighter lobe center value].

So just compensate when you degree them, keeping that in mind. Anything in the 106 - 110 range will work fine. I personally set many cams on 108 centers. Avoid going below 106 on the intake because it closes the intake too soon and you could have detonation creep into your life.

LarryC wrote: The rubbing block will add about 2 degrees to the mix. When you install the cover it will advance the intake and retard the exhaust cam. [tighter lobe center value].

Oops! Larry I think you are having an off day or perhaps trying to catch people out ? :lol:
Only the inlet will be affected (advanced) when fitting the cover. The exhaust timing can't move in relation to the crank.
Now! where do collect my cigar :laugh:

If you want to do it right, this is what you need.





If you plan on keeping your bike, you will have to make one sometime.

Wouldnt you want to have the right side open all the way?

zed1015 wrote:

LarryC wrote: The rubbing block will add about 2 degrees to the mix. When you install the cover it will advance the intake and retard the exhaust cam. [tighter lobe center value].

Oops! Larry I think you are having an off day or perhaps trying to catch people out ? :lol:
Only the inlet will be affected (advanced) when fitting the cover. The exhaust timing can't move in relation to the crank.
Now! where do collect my cigar :laugh:

In the theoretical world it might work like that. In the real world it's a different story. Chain slack develops arbitrarily in the chain. The exhaust cam can rock backwards just as easily as the intake cam can rock forward. The difference being that installed correctly with the tensioner plunger removed, the majority of slack is on the intake side. There can and with a used chain, be slack on the exhaust side as well. The amount is entirely dependent on the age of the chain.......hence the term "about 2 degrees". You want it exact then cut up a cam cover or build a jig. I didn't occasionally work on J motors. I lived with the oil leaking things on a daily basis from 81 through 87.

I had Peters cams in my hands. I know what they measure. I know what they'll do performance wise. Anything from 106 to 110 lobe centers will work. You could get that by bolting them on stock sprockets with a good tight chain..... I'll wager $100 that if I setup two J motors with the same cams, one on 106 and the other on 110 centers then let 10 guys ride both bikes back to back they couldn't identify which was which by any measure beyond a lucky guess

In this particular case you can't bolt them to stock sprockets because they are 3 bolt units but the overall scenario is still applies. If they were GPz vs stock J cams you could and be fine with it...

True, it'll vary minutely due to uneven chain wear no matter what, so I wouldn't even bother trying to compensate for anything on the exhaust, especially as you say, any difference would be undetectable and it would still vary by the same amount anyway totally unaffected by fitting the cam cover.
The inlet is the one that could be gotten a fair way out but then again I wouldn't even bother trying to dial in the cams at all without a top runner jig ,the whole point of degreeing them in would be wasted if you can't be sure to get them where you want them.

x's 2

THINK for a second.... Kawasaki doesn't want the cam cover installed with the side plunger installed [stock tensioner]. Why is that? What'st he issue at hand?

OVER TENSION....... Now that can't happen unless both cams can move when the cover is installed. IF only the intake moved then there would be no over tension issue. The plungers would back off as the cover was tightened down..... BUT...they don't so you end up with an over tight chain.

I have a J on the bench right now for a complete rebuild. I'll post some pics when I get to that point. Crank and trans are not back yet...

Both cams can move when the cover is fitted but the relation between exhaust cam and crankshaft cannot alter.
Only the inlet can permanently vary in relation to the crank and exhaust when the cover is fitted if the degree figure for it is guesstimated with no top runner jig fitted.
A correctly degreed in figure for the exhaust will remain the same whether using a jig or not as the front chain run is constant (discounting minute chain wear)
He should fit the top runner jig first then the tensioner so as to tension the camchain as in normal operation for cam degreeing. ( fitting the cover after the tensioner has not been mentioned or inferred in any post )
You cannot accurately degree the cams without the jig and tensioner fitted as the cams won't rotate smoothly due to valve spring pressure causing them to flick over at the first sign of slack.

Guess I will make one then.

zed1015 wrote: Both cams can move when the cover is fitted but the relation between exhaust cam and crankshaft cannot alter.
Only the inlet can permanently vary in relation to the crank and exhaust when the cover is fitted if the degree figure for it is guesstimated with no top runner jig fitted.
A correctly degreed in figure for the exhaust will remain the same whether using a jig or not as the front chain run is constant (discounting minute chain wear)
He should fit the top runner jig first then the tensioner so as to tension the camchain as in normal operation for cam degreeing. ( fitting the cover after the tensioner has not been mentioned or inferred in any post )
You cannot accurately degree the cams without the jig and tensioner fitted as the cams won't rotate smoothly due to valve spring pressure causing them to flick over at the first sign of slack.

First
These are slider shoes from a J motor. What happens to them is they wear..... BOTH of them. Chain slack exists on the exhaust side as well as the intake side.

Second your description of the valve spring flicking the cam at the first sign of slack incorrect as well. If you were to degree the cams with or without the jig, the complete tensioner should be installed in the engine. After timing the cams you would remove the side plunger and spring to install the cover then install them after the cover is on. It's assumed he knows that already because :

A - it's been discussed to death for over 10 years on this site.
B - He's owns and works on his own collection of Kawasakis and he's got quite a collection...

If you were to attempt it with the OEM tensioner installed but no side plunger AND if you had a horrendously stretched cam chain, then yes, your interpretation would apply.

Third
Installing the cover was inferred in the original post. I'm baffled as to you you could misconstrue that simple fact.
Fourth

When the cams both move by installation of the valve cover then the relationship between the cam and the crank changes. It changes proportional to the amount of slack in the chain, be that by stretch or shoe wear.

Lastly....Yes...make one. Do it properly Peter.

Zed...I don't disagree with your theoretical views but I know what I've seen with my own eyes from building and maintaining these motors BTW your first two statements totally contradict each other :woohoo: