Many of the regular readers will know that one job I've been delaying for well over a year now has been the roll bar.  I've lost count of how many times I've drawn this, then made mock-ups in foam board and plastic pipe to try and find a solution that is both functional and aesthetic.   The problem is that the original roll hoop on the JW4 was 3/4" diameter tube with a couple of basic braces as a token gesture to add some stiffening.  Those of you who are active in sprinting on may rea