TOPIC:

You need to adjust the valves prior to performing a leak down test.

Indeed-- all roads seem to lead to valves. Thanks.

Absolutely. If the clearances are too tight, the valves will not close completely and all readings will be off, performance down, etc.

No eBay APP ID and/or Cert ID defined in Kunena configuration

Flatblackobsession wrote: Anyone know what tool (if any) I'd need for shim work on this bike (Kz1000e shaft)? Also, what shim sizes might I be looking at with this?

If a tool is needed, is this the animal I'll need:

Anyone ever use one of these before?

These work O.K. in a pinch. However there is a Kawasaki tool that is much more precise. You wont know what shims you'll need until you get yours out. You'll have to = or- according to your readings. Measure your gap. then ad the size to the next, larger shim. If you encounter a shim that it over tight. Install one two sizes smaller and then re check. It's not hard, but you need a selection of shims, a good quality shim tool, a strong stick magnet and a small pointy screwdriver. Even with experience, the K&L type tools will shoot across the room...crack shims...spit out shims...But, if you wont be doing this job often, maybe the low price would make it worth while. I wish I were closer.

Just my 2 cents.. If an engine that has been sitting is fired up and smokes untill it warms up, generally, it has bad valve stem sealing. guides, seals, both. While the bike is sitting, oil seeps past the guides and pools behind the valves and as they open, into the combustion chamber causing the smoke on starting. If an engine smokes on acceleration/ deceleration once warm, it is most likely a ring sealing issue. Overly worn rings, glazed walls, broken ring or worn sleeves. oil is pulled up and pushed down past the oil control rings and into the combustion chamber. the crank case is pressurized by the "blow by" and this also causes oil to be places where it does not belong. I think that your engine is simply wearing out. It's very likely that it can be honed, re ringed, and that a valve job would help it out. This can be done by a novice. I think it's what you need.

Zero, do you have a part number for the Kawasaki tool?
I have shim under bucket, so I don't need one.

I missed that, koolaid. The shim tool is for shim over bucket. I work almost exclusively on them. Are you SURE you're shim under bucket? A 1980 should be shim over and the kawasaki tool is:#57001-113. you can find copies on Ebay. They're still easier to use and much better than the K&L. If you have a 1980 KZ1000 and its shim under, someone has been in there and you may have some performance parts. ??? (I just saw that you have a G.P,Z.750..nevermind. sorry) Also, Z1 enterprises actually sells the knock off Kawasaki tool.

I'm not the OP, I've just been working with him up to that point, then I told him to pose the question in his thread,which you answered but did not give him a part number.

ZERO wrote: I missed that, koolaid. The shim tool is for shim over bucket. I work almost exclusively on them. Are you SURE you're shim under bucket? A 1980 should be shim over and the kawasaki tool is:#57001-113. you can find copies on Ebay. They're still easier to use and much better than the K&L. If you have a 1980 KZ1000 and its shim under, someone has been in there and you may have some performance parts. ??? (I just saw that you have a G.P,Z.750..nevermind. sorry) Also, Z1 enterprises actually sells the knock off Kawasaki tool.

Yes my 80 KZ1000 is the shim over and I bought that same tool off of Ebay. It works great.

Will that tool work on a '79 750 twin? Part number is different.

650ed wrote:

Flatblackobsession wrote: Right-- very baffling. So, the question would then be: how much of a compression increase (i.e. "drastic" compression increase) indicates oil action on the rings, as opposed to displacement? A hell of a mystery.

I also put a little more than a teaspoon in there-- maybe 15-20 milliliters, but it was the same amount in each cylinder, so it makes me wonder if that isn't why there was this uniform psi increase-- regardless of base cylinder readings.

Any and all thoughts on experiences/theories are appreciated. I really want to get to the bottom of this.
Thanks,

That seems very logical to me. I would think that if all the rings are holding compression well, the same volume of oil added to each cylinder should result in the same increase in compression readings. I would try a leak-down test to see if you can detect compression leaking from the exhaust or intake valves, or if it's leaking past the rings into the crankcase. Ed

You are absolutely correct, oil added reduces the combustion chamber volume, increasing compression.

If the rings are bad and you add oil, you will see at least 50 psi increase, the most I've ever seen was 140 psi increase.

Sorry, Topper. Can't say for sure. I know that the cheapy K&L tool fits the 750 twin, but the Kawasaki part clamps onto the head and holds the edge of the shim bucket and the shape of the head is critical.It's very likely that the Kawi tool will not work, but also likely that another tool exists from them. Ages ago, when I was a KAWASAKI tech, we had tools that absolutely NO-ONE knew what they were for....

Topper wrote: Will that tool work on a '79 750 twin? Part number is different.