cam chain tensioner

I have a 83 650. I am wondering if there is a procedure for adjusting the cam chain tension

Automatic tensioner. Known to jamb up on occasion so you might want to verify yours is functioning as designed.

Best to put the engine at 1-4 TDC before removing tensioner to check.

No eBay APP ID and/or Cert ID defined in Kunena configurationYou might want to consider getting a manual tensioner. ApeRacing & Krieger.

If you need a service manual, search eebbaayy for KZ650 manual. Don't get a clymer.
Although your bike is the 83 model, you can probably use the 81-82 KZ650 manual.
KZ650.Info - Factory Service Manuals and parts list info - see reply #52 for info about the 81-83 manual

In the mean time, the Files page of the following site has the 81 650 pdf manual.
jarlef z650



1983 KZ650 supplement page for the F4/H3 models:

Is the small screw on the side a locking screw? Does it have to be loosened to realease tentioner? Or does it work without touching anything.

Do not remove that small bolt - it fits into a groove of the push rod to keep it aligned & keeps the push rod from falling into the engine. Since it's pushing against the cam chain guide, I don't think it'll fall in, but the manual has the warning & removing it won't do anything to reset it.

I believe you can reset the tensioner by removing the wedge, but you should read up on the tensioner carefully before doing anything. The wedge is under the big cap - you need a 17mm socket to remove the cap.

I'm assuming your tensioner is the Cross-wedge type (there is also a ball-lock type mentioned in the manual).