Which head gasket for GS750 with 69mm pistons?

[Coady]

I've got a set of GS850 cylinders and pistons to go on my 1979 GS750.

Will an OEM GS750 head gasket have a wide enough inside diameter to fit these or should I get an 850 head gasket? The 750 pistons are 65mm and the 850 69mm.

I'm looking at both on ebay and the 750 gasket has rubber(?) type rings on the outside bolt holes, whereas the 850 doesn't.

I currently have this OEM GS750 gasket at the moment with the built in rings and have had no leaks, so I would prefer to get the same again.

Thanks

[TeamDar]

Use the 850 gasket.

[Coady]

Use the 850 gasket.

Very well. So those built in rubber rings aren't necessary?

[ojocher]

All the rubber o-rings are necessary to keep the oil in the galleries.
also check that the aluminium material around where these o-rings sit are good....if not get a guy who's good with aluminium to weld this material back into place otherwise you will have a leak...I did