Agree with the above...Best way in my opinion would be to run the cable all the way under the tape.

If that isn't an option (it wasn't for me) then just wrap over the cable for the first 3-4 wraps, then over just the bar. Where you make the transition, cut a small notch in the tape so that you can continue overlapping the tape. It's hard to describe, but you may understand when you start wrapping.