KZ550 engine with low compression

I am new here. I used to have a KZ 440 AND A KZ750. both bikes are now gone. I am looking at a 84 KZ550. The bike is complete, about 32k on it. I was told it has low compression on all 4 cylinders. It does spin freely. My question is has anyone have any experience with these? Just need advice as to whether it's worth me picking the bike up. I was told best case scenario is it might be in need of a valve adjustment and a carb rebuild. Worst case a full tear down of the engine and rebuild.

Every time I've been told a Kz550 had low compression, it turned out the motor was fine. The problem was either an error during the compression test or a faulty tester. I pickup up a Gpz550 dirt cheap because the owner's tester was faulty. I showed him the engine was fine with two other testers, but he still sold it to me cheap.

I am thinking the same thing. I am quite sure that the guy took it to a shop that only works on American bikes. They did a quick test and blew it off. I will have the bike after Easter in my garage. First thing I am going to check is the compression my self. I plan on ordering a shop manual next weekend also so I get the proper procedure down.

If the valves are hanging open because they were not adjusted recently you will get low compression.

In the meantime, if you follow the links in my signature, you can find several service manuals for Kz550's. I would download them all.

So bike is in the garage now. I had a look over again. It has new tires, LED signal lights, new paint on the tanks and rear fender. Fual tank looks to have been cleaned out and sealed. I suspect that carbs have been serviced also. So next step is to measure valve clearance, I need to order a feeler guage. Does anyone have any recommendations for what to get?

I have down loaded all the links to my phone, I also got a Clymer manual with the bike.

NAPA makes a nice metric set of feeler gauges. If you want to convert to US measurements, your friendly neighborhood auto parts store should have a set. I am too lazy to do the math, so I got a metric set.

Also, you need this.
www.kzrider.com/modules/ServiceManuals/Kz400500550_79to83.pdf

Before opening the valve cover, please read the valve train warning page in my signature. It will give a lot of tips for checking valve clearance.

Tank sealer has always been a bike killer in my book. Nothing but troubles. If they use the the wrong stuff you can be forced to clean the carbs weekly. I'm going through that now. There does not seem to be any satisfactory way to get the rank liner out.

I am going as much reading as I can before I touch anything. The one thing I keep noticing is that there are a lot of links to the 79-83 KZ550. Are they the exact same as the 1984.

Depends which 1984 model you have, which might be affected by where you are. In the U.S., I think the only Kz550 would be a shaft drive Kz550F2 Ltd. By 1984, the Gpz550 was a Zx550A1... no longer a Kz, but still similar enough.

The shaft drive models have enough differences that they use a different series of factory shop manuals, but the engine internals are basically the same, and even the carbs are somewhat similar to the 82-83 Kz550H1/H2 and 84-85 Zx550A1/A2 (all Gpz's), so the third-party shop manuals lump them together. The valve train page applies to all of them with differences as detailed on that page.