Timing issue

Hi all I had a rear head issue which required a replacement but when I went to set timing I found that both front and rear were out by about half a tooth so moving back or forward a link didn't line it up with the timing notch exactly. Talking to a few experienced bike mechanics hasn't clarified if this is ok or not as one says ok and one says not. If not what would cause this. Chains are in good condition . Xvs650 dragstar Classic . 2003. Thanks for any help