Replacing piston rings

[xs650newb]

Hey all,

Currently tearing down my 1980 650 to replace the front cam chain guide (if anyone has a new one and is willing to sell it please pm me).

While I am in there I am going to replace the valve guide seals and of course the bottom end and head gasket. To get to the bottom end gasket I have to remove the jugs which means removing the pistons from the jugs.

Am I required to replace the piston rings if they are removed from the jugs?

The engine had great compression before tear down, fyi. Something like 150 in each cylinder.


Best,
Adam

 

[5twins]

No, it's not required. If they're in good shape and the end gaps are not too large, you can re-use them. I've done so on several motors. However, the majority of the ones I've had apart had end gaps too large and needed new rings.

 

[xs650newb]

Thanks 5twins. That is good to hear.

Also, I am slightly confused by gaskets and o-rings. Do I need to replace any gaskets or o-rings besides the bottom end gasket and the head gasket?

 

[retiredgentleman]

Hey all,

Currently tearing down my 1980 650 to replace the front cam chain guide (if anyone has a new one and is willing to sell it please pm me).

While I am in there I am going to replace the valve guide seals and of course the bottom end and head gasket. To get to the bottom end gasket I have to remove the jugs which means removing the pistons from the jugs.

Am I required to replace the piston rings if they are removed from the jugs?

The engine had great compression before tear down, fyi. Something like 150 in each cylinder.


Best,
Adam

Actually, you don't have to remove the pistons from the jugs if you don't want to. Just lift the cylinders until you can access the wrist pins. Remove the spring clips and take out the wrist pins. Pistons can stay inside the cylinders.

Realistically, for the work involved removing the engine, it would be smart to have a good look at the pistons/cylinders/ and rings as 5twins mentioned.