Cylinder compression test - failed ??? :(

So my compression tester from ebay arrived and I just did a test on my engine. And I'm happy to report that the compression on each of the cylinders is ~145 psi.

Please ignore all my complaints about all sorts of things because I didn't know anything about any of this then. Thanks to you all, I learnt a lot about how an engine works, compression etc etc etc.

Glad to know that I have an engine that may have some good life left in it.

I have 179 - 184psi in a cold engine. Isn´t 120 - 145psi very low?

The specs on these thigns are pretty wide. I know on my 750 Spectre, the spec was from like 130 to 190. It was really looking mroe for whether they were close to each other. Some of it will be influenced by stuff like your intake and your valve settings. The more air you get in when all the valves are clsoed, the higher the compression will be, so there's a fair amount of variability.

Del_Herring wrote: The more air you get in when all the valves are clsoed, the higher the compression will be, so there's a fair amount of variability.

Hmm and I didn´t know about having throttle open so I guess my values are very good (refurbishing valves and seats helps . And yes it is most important that the diff. between cylinders doesn´t deviate more then 14psi (on KZ550).

I would say that anything above 120 PSI is fully acceptable, and even as low as 100 PSI engines can deliver close to full power, depending on what cause the low pressure.

I was going with the KZ550 manual which said the pressures should be anywhere between 120 to 150.