How to check if cam chain (auto) tensioner is OK?

I have this rattling noise from the engine. Which I guess could be the cam chain that is not enough tensioned.

I think that I have a auto tensioner. How do I check that it works as it should?

I've heard that I measure the tension between the two top gearwheels. Correct? Can someone help me with some numbers?

If the tensioner is broken. I was thinking that I buy (or build) a manual tensioner. Any pros /cons with a manual one?

Bike: z/kz 750 1982 (E3). Four cylinder.


(What is the difference between Kawasaki Z750 & kawasaki KZ750? I have a Z-version..)

Thanks!

The primary difference is that the US versions were all called "KZ" while the ones sold in i Europe and Japan were called "Z." There may be some minor differences in lighting, etc. based on legal requirements of the country to which the bike was shipped, but in general they are the same bike. Ed

Good question......I'd like to know as we'll about the auto cam tensioner.

The tensioner can be rebuilt, it is very easy to do. And it is automatic, the manual ones are a PITA.
I had to rebuild the tensioner on my GPz, took me two times before I got it working properly but works great now.

You check it by removing it and seeing if it works smoothly without any hitches. It should be very easy to move in and out without any hitches or catches.