Valve adjustment advice

0.004 inch == 0.1016 mm

The service manual specifies the proper clearance as 0.05 to 0.1mm, so you're saying ideally I should aim for the high side of the tolerance band when I re-shim?

This is great info btw...I don't understand all of the precise workings of the valves and such but I'm getting a great education so far! I'm glad I'm doing this myself -- so far anyway. We'll see how the thing runs after I'm done screwing with it.

Back in the drag racing days most the guys preferred .10mm, basically .004" in American size. Really though how much duration of cam difference can .002" really make? 2 degrees max? I can't imagine a noticable difference in performance myself. I've ran .002", .004", .006" clearance over the years and I could always tell a whopping zero difference between them in performance, but I'm not the most observant guy.

Shim to achieve the most valve lash clearance possible within spec. The clearance CLOSES as the components wear and max lash will allow you to go the longest between adjustments. You can actually open the clearance up a tad more than .1mm... Jeff Saunders z1enterprises.com made some good observations when we were on the old forum... hopefully he will chime in.

To be precise, i had 2 cylinders that that were less than .001. I consider a bucket and shim essembly to be a lifter. I could see daylight between the base circle and the lifter or shim. A .001 feeler gauge would not fit. I fitted the motor with a dial and wheel. found tdc with a stop, noted op. and close numbers. The in. op. before 30 degrees (spec). This is earlier. In. cl. 80deg (spec 70deg) That is later, shifting the power band higher. If you have 2 cyl. .0005 clearance, peak power output for those two will occur at a higher rpm than the two with stock op. and cl. timing. The motor it can be said has a best of two world charactoristic as the power band is no longer linear. The cyldrs. that have stock timing support the band in the low mid and high (to 8500rpm) range where as the the other two will have less output in the low to mid earea (not supporting the other 2 clndrs there) the high rpm output can exceed that of the stock 2, causing the motor to accelerate harder than normally would be possible. If you run too much clearance, the valves have no choice but to rocket open and slam shut. When they do they stress the lobe surface, smash the valve seats in reducing clearance.

Post edited by: nads.com, at: 2005/12/11 16:02

Post edited by: nads.com, at: 2005/12/11 16:04

I had over 200lbs of compression in 2cyl. The valve specs were on. The other two had 180. These two had less than .001. Changing the clearance to .004 raised the compression to over 200lbs. Come to think of it the 2 low cylinders had less than 180 like 170 or so.

Post edited by: nads.com, at: 2005/12/10 23:20

If you can't get a feeler guage under the cam check to see if the bucket will spin - if it does then you have some clearance - so you can assume slightly more than zero for calculation purposes.

Originally Kawasaki listed 2-4 thou (0.05mm-0.10mm) as the recommended clearance. On later models the increased the max recommended clearance to 6 thou (0.15mm). As clearances reduce with wear on the engine, I would typically try and get all of them in the 3-5 thou range (0.075mm-0.125mm) range - I never leave a clearance at 2 thou (0.05mm) as the next time you check it the gap will likely be under spec.

If the bike had been sitting for a while, you may have some corrosion in a few of the valve seats - most of this will disappear once the bike runs - but you will probably 'chase' the clearances for the first few hundred miles.

It is probably worth running some ringfree or seafoam though the bike after you have set the clearances - this will help remove any carbon deposits from the valve seat area - again, this may cause you to adjust the clearances within the first hundred miles or so.

I can't get a .04mm feeler gauge under the cam lobe on any of the valves, but I can see light in there and the buckets spin freely. I bought a 2.00mm shim from the local dealer and temporarily installed it in a few valves to try and get an accurate clearance measurement. The clearance on a valve that originally had a 270 shim was .70mm with the 200 shim -- so following the chart in the service manual I ordered a 265 shim for that valve. Basically I ended up ordering the next-smaller size for all of the valves, since they all followed this pattern.

This bike did sit for a number of years some time ago, but I've had it running fairly well for the past 5 or 6 years. I've probably put 6,000 miles on it in that time. Should I still run some seafoam through it, or would that be enough time to have burned off any remaining crud?

The #3 or #4 cylinder (not sure which one) always has a hard time getting going when I first start the bike. It smokes a bit when the throttle is revved, and you can hear the miss in the exhaust. It gets better after the bike has run for awhile. I'm doing this valve adjustment and I also did wiredgeorge's wiring mod to power the coils through a relay (haven't run the bike yet after that mod). The carbs have been cleaned a couple times and new rebuild kits installed, so I'm pretty sure everything there is good.

Anything else I should be checking?

IMHO one of the best investments you could do the ANY bike with points is switch to electronic ignition,I had a kz900 back in the day that would start on 3 cylinders and it would SOMETIMES clear out with the points,I switched to a factory electronic ignition and the problem went away.

just my .02

yeah I made that change a few years ago, it was a HUGE help. Well worth the investment.

Newbie here. Very good thread with lots of info. My KZ1000 has 70,000 miles on it and only two of the valves show a gap of which is 0.004 and 0.0025. The rest you cannot get a feeler gauge under but you can turn three of them with your finger. This leaves three that have absolutely no clearance. What size shim do I need to use to test the gap? I saw earlier vdrumman used a 2mm. Do I need to get a smaller one for the other three or will a 2mm work?
Thanks for the help.

The best thing is to buy just the shim tool first - then go through the valves and log all the clearances and shims. Provided you can spin the bucket you have some clearance - so assume one (1) thou for calculation purposes. If the bucket does not spin, then you can probably assume negative one (-1 thou) and calc from there.

It's best to try and get the clearances around 4 thou.

With the original shims in place each of my valves would spin freely and I could see a small amount of daylight. However I couldn't get my feeler gauge under there to get a measurement. So I purchased a 2mm shim, which I believe is the smallest you can buy (Jeff may know better) in order to try and get a good measurement to use so I could calculate the exact shim sizes I needed. This resulted in me deciding to just purchase the next smaller size for each valve.

And now from the "stupid thing I did that you hopefully won't repeat" department -- after I got the new shims and began installing them, I noticed that I still wasn't able to get my .05mm feeler gauge under there even with the new shim. So I took a closer look at my feeler gauge and discovered (duh) that I was actually measuring with several of the very small sizes all clumped together. Those suckers are VERY thin and it's real easy to accidentally not get them all separated. FWIW, the feeler gauge set I got from z1enterprises has the following sizes -- if you don't see all of these, then double-check to make sure they are all separated:

.04mm
.05mm
.06mm
.07mm
.08mm
.09mm
.10mm
.15mm
(plus a bunch of larger ones)

After installing the new shims, my clearances all measure out to be within spec, which is .05mm to .1mm on my bike. There is still about 2 feet of snow on the ground around here, but as soon as it clears I'm going to take the bike out and see if it runs any better.