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Valve adjustment on my ZRX (anyone want to check my math?)


thomez

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This is an 03 ZRX1200 that has just a touch under 45,000 miles - I bought her last summer and unfortunately don't know much about the service history. I rode it a touch at the end of the summer but had a wheel bearing go out and never got it back on the road. Figured I should get this maintenance thing done before flogging her all summer!

Spec is -

Exhaust - .0070 to .0095 (apparently .010 perfectly acceptable)

Intake - .0050 to .0075 (apparently .0080 is perfectly acceptable)

Anyways .... here are my measurements.

Left to right, E for Exhaust, I for Intake....

E1a - .006 - shim .104

E1b - .005 - shim .104

E2a - .006 - shim .105

E2b - .005 - shim .106

E3a - .002 - shim .106

E3b - .002 - shim .1055

E4a - .0075 - shim .103

E4b - .005 - shim .104

all intake shims were .102 .... leads me to believe adjustment may have never been done? seems odd they are all the same ?

if anyone can add to that analysis it would be appreciated

I1a - .005

I1b - .0025

I2a - .005

I2b - .005

I3a - .0025

I3b - .0025

I4a - .008

I4b - .005

Doing the math now to make sure I track down the correct replacement shims.

Let me do Exhaust #1a and you can check my math, please?

Shim = .104

Measured Gap = .006

Desired Gap = .010

Desired Gap Change = .004

This would mean I need a .004 smaller shim, which would be a .100 or a 2.55mm

correct?

Here's my math for the rest of them.

Exhaust

1a - .104 shim changed to .100 shim makes gap change from .006 to .010

1b - .104 shim changed to .100 shim makes gap change from .005 to .009

2a - .105 shim changed to .102 shim makes gap change from .006 to .009

2b - .106 shim changed to .102 shim makes gap change from .005 to .009

3a - .106 shim changed to .098 shim makes gap change from .002 to .010

3b - .1055 shim changed to .098 shim makes gap change from .002 to .0095

4a - .103 shim changed to .102 shim makes gap change from .0075 to .0085

4b - .104 shim changed to .100 shim makes gap change from .005 to .009

Intake

1a - .102 shim changed to .100 shim makes gap change from .005 to .007

1b - .102 shim changed to .098 shim makes gap change from .0025 to .0065

2a, 2b, and 4b are the same as 1a

3a and 3b are the same as 1b

and somehow, some way, 4a doesn't need any change at all .... just fine at .008

so, uhh.... how's my math? should I make these intakes .0065 or should I go to .0085 (out of spec high) ?

anything you would do differently?

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there is a nifty chart in the r6 service manual that helps with shim replacement.

do you have a service manual? i would think this kind of info would be in there.

here if you dont have one:

http://pdftown.com/Kawasaki-ZRX-1200-Service-Manual.html

Edited by natedogg624
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.0085 on the intake side is a thousandth out of spec (too high) so I figured it was best to avoid going that far out on purpose

If it says that .008 is acceptable, .0005 too high isn't really that much.

I'd probably try to get as close to the max as you can.

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If it says that .008 is acceptable, .0005 too high isn't really that much.

I'd probably try to get as close to the max as you can.

well .0075 is the high end of spec, so I didn't know if .0085 would be too much because that's a full thousandths out of spec .... the .008 was said to be acceptable because it was only .0005 out

what do ya think?

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well .0075 is the high end of spec, so I didn't know if .0085 would be too much because that's a full thousandths out of spec .... the .008 was said to be acceptable because it was only .0005 out

what do ya think?

Too tight is bad, looser is better. I would say get it as close to the max as you can, without going over.

Really, you're not THAT far out now, and the bikes got 45K on the clock. How long since its last valve adjustment?

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Too tight is bad, looser is better. I would say get it as close to the max as you can, without going over.

Really, you're not THAT far out now, and the bikes got 45K on the clock. How long since its last valve adjustment?

No idea. I just bought it at the end of last summer and didn't get much info, the guy hadn't had it long.

All of the intake valves had the same shim, which led me to believe maybe they had never been done? No clue really.

Most of them weren't TOO bad, but some were quite tight at .002 and .0025 ....

I was trying to get as loose as I could without going over, which is why I was going with .0065 rather than .0085 (which is over by .001)

Edited by thomez
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No idea. I just bought it at the end of last summer and didn't get much info, the guy hadn't had it long.

All of the intake valves had the same shim, which led me to believe maybe they had never been done? No clue really.

Most of them weren't TOO bad, but some were quite tight at .002 and .0025 ....

I was trying to get as loose as I could without going over, which is why I was going with .0065 rather than .0085 (which is over by .001)

The shims all being the same really doesnt have much to do with it being done "recently" or not. Its possible the PO had the seats cut and put new valves in. Unless you have the information, its really impossible to guess.

I'd say put them at .0065, if thats the best you can do. .0005 over isnt bad, but you dont really want to go way overboard.

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The feeler guages I have are from like .001 to .010 (i think). Is that what you guys use on your bikes? I am wondering if i can or should get some that are more accurate or have smaller or in between increments.

I use metric feeler gauges. As well as SAE. And you can double the feelers and use two at the same time, to get other gap measurements.

The important part is to develop a feel for the right amount of drag on the feeler gauge. If you drag it too tight or too loose, it will be a false reading by a small amount. And keep them clean, wipe them off each time you use it. We don't want grit in the engine. Grit bad.

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The feeler guages I have are from like .001 to .010 (i think). Is that what you guys use on your bikes? I am wondering if i can or should get some that are more accurate or have smaller or in between increments.

ya in increments of .001

(when I had .0025 listed it was because .003 wouldn't fit but .002 seemed a little loose, lol)

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Yeah that s where im at. My intakes are sopposed to be .007 to .009 and the .005 is hard to get in, like wont clear at all and the .004 seems too easy, but it still has a little drag. You should be able to get teh bend of the guage all the way past the cam lobe and through the other side right? these are the first two i am checking and they are WAY out of spec..... Im just making sure that i shouldnt buy better feelers..

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the bend of the gauge? the ones we used were completely flat .....

on my bike you want to get them between the shim and the rocker

a little drag is accurate, a lot of drag or sloppy loose is inaccurate, at least that's how I understand it

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I am getting the feeling of it a bit. The .005 wont go in but the .004 will. But I can feel if it is easier to get past the cam , or it feels the same sliding back and forth, but some it seems like there is a little too much drag on the guage. Mine have a slight bend at the end of each guage, they are not completely flat. they look sort of like this: ____/ only not such a extreme bend.

My valves have buckets that the shims are under. This is definitely different than the Ninja 250 valves when i did them. This seems easy though, just check the clearances and write them down, then check them three more times just to make sure the numbers are right, then you just pull the cams, check the thickness of all the shims and do the math for the differences, then just triple check the numbers again and put all the right shims in all the correct places and button them up. Seems easier than the 250 valves in the sense that you dont have to check clearance, adjust the valve then rotate the engine and do it again. As long as you get all your numbers right you just put in the correct shims and you should be good to go. If as many of mine are off like how they are i think i just wasted money on the shim kit, im betting i am going to need more than three of some of these shims, and thats all that came in the kit. Ill have to see after i do the math. Every one i have checked so far have not even been close to what the clearances should be.

On the bright side it should run beautifully when it is all done. If they were that off it should feel like a brand new bike.

I just saw that on some of these shims HOT CAMS is spelled HOT CMAS. oops...

Edited by Mc_spirited
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