When ever I back my bike up it rolls free for a couple of feet then starts to bind up. I've traced the issue the belt walking into and binding against the engine case when the rear tire spins backwards. From all of my measurements the rear tire appears to be straight.

Is this usually an alignment issue or a sign of another problem?

 

As long as it rides in the middle of the pulley going forward, you're fine.

 

Unless the trans drive pulley is loose, damaged or warped....thats another story.

The belt should never rub against the engine or anything else.
The rear belt walks in & out based on the alignment of the rear wheel/pulley.
Get the rear wheel off the ground, spin the tire & look at the movement of the belt.
Check the rear pulley bolts for tightness, a loose pulley can also do this. Retorque as needed.
Make minor adjustments on the axel alignment until the belt moves slightly in & out on the pulley.
Retorque the rear axel to specs & re-check belt movement again.
You should be good to go.

 

Thanks for the info

The rear sprocket is tight. I tried adjusting the rear alignment a little with no effect on the belt. I'll play with it some more.

Thanks again for the help.