Very slight play is normal. You have an excessive amount. I would shim some of that out. First tighten the nuts though, maybe that will eliminate some of it at least. I had what I considered too much play on mine, mind you not nearly as much as yours, but more than I was comfortable with. My timing mark jumped around a lot at idle. I shimmed it out, leaving only maybe like .006" to .008" (to allow for expansion once hot). This cured than bouncing timing mark which made the bike run a little smoother as a result.