O-rings on bottom of cylinder sleeves

On my 77 KZ1000 there is an o-ring around each of the cylinder sleeves. I didn't see these for sale at Z1Enterprises. How important is it to change these? Mine appear to be in decent shape.

Also, what are the rubber plugs for on the bottom of the cylinder? I don't have the cylinder in front of me right now, but I think they are about dime size. I'm missing one and the others are loose in their holes. Are these vital?

call z-1...they can get anything..


man, i m having a brain fart on the second question..:laugh:

If you purchased a complete gasket set for your KZ1000A1, the rubber o-rings on the bottom of the sleeves were included. If you have the jugs off, replace them...mine were very brittle on both my KZ1000A1's...but they looked good

The rubber plugs are to reduce harmonic vibrations. While they don't have anything to do with the motor actually running, I have heard of folks who didn't have them and there was an irritating vibration/noise at certain rpm's.