Just a small local event.

[johnboy]

Are roll bars required in New Zeland? It looks like every roadster has one

Not insofar as I'm aware. They are mandatory though on the drag-strip; so if you're contemplating taking your car down the strip it's a good idea to build them in prior to certification. Certification is quite expensive, and to retro-fit them would require re-certification.
Our Cobra was fitted with a roll bar when it was built, bit it's not now legal on the strip, as it's only shoulder height whereas the rules/law now state they must be above head height and be mounted to at least three points on the chassis.
But our Cobra was built prior to certification, and is running on a declaration.
That may sound complicated; but if you've grown up with the system it makes sense.
Initially, in the late fifties you could build a car and if it passed a warrant of fitness you were good to go. But too many badly engineered projects were getting through the system and being driven as 'an accident waiting to happen'.
So the declaration system was brought in; where all you needed was for a competent engineer to inspect the car and declare' in writing that the vehicle was basically safe to be driven.
But too many badly built/engineered projects still got through.
So the certification system was brought in, where a trained specialist engineer licenced by LVVTA (Low Volume Vehicle Technical Assoc) would make an extremely thorough inspection of the vehicle and any remedial work before signing it off.
Our car would pass certification; but being the impoverished peasant that I am I'm not about to fork out many hundreds of dollars to get it done.
Added to that; because our bus has a chassis rating of over three tonnes, it had to go through NZTA (NZ Transport Assoc.; they do the hgv's) and they dicked me around for better than twelve months. It took an investigation by TV's Fair Go team to finally get them to rattle their dags and sign it off.
So I'm not going to open another potential Pandora's box thank-you-very-much!
I'll stick with the declaration!