Z1OwnersClub GB

Due to debris in crankcase I have decided to remove the cylinder head to check the camchain guides. I have now discovered I have a z1000 head on 903cc barrels, will this have a detrimental effect on anything and which head gasket should be fitted. Thanks in advance

No detrimental effects whatsoever, it can only be better as you've less chance of snapping the exhaust studs and just use standard gaskets.
There's a good chance that an idler has collapsed due to the plastic insert giving up my old Z1000 did this but still ran pretty well when they do collapse the idler rattles around on it's shaft and grinds into the barrels.

Cheers, that's a relief. Did notice that half of one of the damper rubbers on the idler had disappeared (new ones ordered).