Am I missing a spacer?

[borjawil]

78 xs650 (hard tail), rear disc wheel. from left to right on the rear axle I have:
chain/wheel adjuster, wheel collar, wheel, caliper bracket, chain/wheel adjuster

I feel like theres another wheel collar or spacer that needs to go on the right side of the wheel before the caliper bracket.

 

[fox23]

You are correct. There is a spacer required between the wheel and caliper bracket. They aren't that easy to come by (in my searches a few months ago anyway). I had to machine one out of aluminum, if you need one PM me.