As you know the S30 has a dedicated battery bracket frame. Does anybody know/make a battery hold-down bracket to fit the Red Top Optima battery?

this is hat came with my zed. it's just an aluminum flat bar.

I posted the solution complete with CAD drawing on here a year ago. Check it out.

I did modify the bracket slightly from the CAD drawing. Rather than having a cantelevered hole, I welded a piece of steel tube for the J bolt to go through. I had to cut just a bit off the J bolt as well. I painted the bracket with wrinkle finish paint and added the loop side of velcro to the back of the angle brackets where it touches the battery. It was simple to make and didn't cost much. All the materials came from Home Depot. For the angle brackets, I started with square tubing and sliced it into angles. Angle iron cannot be used as it is only square on the outside of the angle. The inside has a taper and a radius at the corner. Let me know if you have questions.