mx5cartalk.com

Thinking of getting roll bars for my '99 MX5. Possibly the '2 hoop' type but functional, not just for decoration. Any ideas on the best brand etc. and where I can source them and is it possible to fit them yourself?
Thanks---Wiz.

Mx5 plus, brisbane
Around $800 from memory
You can fit yourself as long as you can use a drill and a spanner.

That's about the only choice In australia for a functional twin hoop.

debatable whether any roll bar for road use is a safety feature- there is simply no real data. As far as I am aware Mazda still do not claim their twin hoop thingo as a safety feature. Buying them for any reason is an owners choice.

So Mr Morlock, you'll wait for an ANCAP survey to tell you if there is any benefit to be had from a well made functional roll bar in an MX-5.

The computer modeling that MX-5 Plus did on the strength of their bars is obviously not enough to convince you, nor the very obvious physical evidence of what happens when an MX-5 rolls over. Perhaps my own experience of being rear ended at speed and walking away unscathed when I could have been de-capitated by the ute tray that hit me is not enough either. Best to wait for someone in ANCAP or the RTA to tell you it's ok I guess, but if you excuse me I'll keep my BD roll bar right where it is, and if I was in the market for another bar it would be an MX-5 Plus one.

Wiz, I'll leave you to draw your own conclusion.

Mr Morlock, I fail to see how that is relevant?

has Wiz asked for opinions on rollbar function? NO
has he asked for if Mazda claim the rollbar on the NC (a completely different model!) is a safety feature? NO

of course buying them is an owner's choice! I don't recall Wiz saying that there's a gun pointed to his head!


the whole debate about rollbars for and against has been done to death. Besides, the whole debate in unrelated to the Twin hoop design as it sits about the same height as the seats!

Ignoring the driver's seat in this image, where it looks to be moved forward for a shorter driver, the bar sits at the same height as the passenger seat!





Morlock, you seem to be a reasonable polite man, and I apologise for being so blunt.

However, Please, read the question being asked and unless you have something relevant to say, then refrain from posting anything!

Hey wiz043

You wont regret the MX5Plus Twin Hoop.
It is a good bit of gear from a professional organisation.
I have had one for couple of years, it is excellent.
It also adds a noticeable amount of rear end rigidity.

wiz043 wrote:Thinking of getting roll bars for my '99 MX5. Possibly the '2 hoop' type but functional, not just for decoration. Any ideas on the best brand etc. and where I can source them and is it possible to fit them yourself?
Thanks---Wiz.

Another vote for the MX5 Plus Bar
Mine cost me about $900ish in October 2010 including painting and delivery to Melbourne.
I initially wanted the 2 hoop but ultimately purchased the single hoop.
Theory being that if you do go over with a single hoop it is less likely to dig into a soft surface.
Lets hope no-one ever proves that theory.

The other functional bar is the Brown Davis bar which only comes as a single hoop.

There are a number of threads on the forum discussing the various aspects of bar design and legality.

Good luck with whichever you purchase and lets hope you never get to use it for it's intended purpose.

MINX wrote:Hey wiz043

You wont regret the MX5Plus Twin Hoop.
It is a good bit of gear from a professional organisation.
I have had one for couple of years, it is excellent.
It also adds a noticeable amount of rear end rigidity.

+ 1 what Minx say's I have the same it looks great and allows easy access to raise the top from the driver seat while seated and after finding how much weight they would hold in the event of a roll over I was sold.
Cheers
Dale

Wiz said "but functional"
That was my point- how does anyone really know how functional these things are for an MX5 used on the road without any data/ testing. Strength of the bar may not be relevant- but how it interacts with occupants in various crash situations is.

I see where Morlock is coming from. Although they may supply support and rigidity in a role, the functionality would ultimately depend on the driver. For me, for example, it would only be functional for chassis stiffness, as my head would be above the bar, therefore not actually offering any protection in the even of a role.
I'd suggest sitting in a seat with one installed, or seeing where your head comes up to when you push yourself up in the seat (simulating centrifugal force or a role). If you go outside of where the bar is, it won't provide head protection, as it'll be hitting the road. However, if they stand up to role as others have said, it will still be more protection than the seat and your head alone.
Those bars look mean, especially in black btw. Very nice.

I've been looking at the MX5 Plus bars, my interest is in structural rigidity for everyday driving and additional side impact strength, rather than for rollover protection. I'm more likely to get t-boned in the city than roll my car. In any case, the twin hoop bars will sit quite a bit higher than the seats on my NB8A, as the seats are not as tall as the NB8B seats pictured. I'm also 6 foot tall, so my head will be above the bar as well. The bars look very well made. Would like to have a closer look before purchasing, but I don't know of any cars with them fitted in SA?

On the subject of being outside the bar's protection - I have personally watched three race cars roll (Winton, Amaroo and Oran Park) in historic racing, where the drivers were taller than the bar. In each case they walked away with minor cuts and bruising. In one case the bar was so poorly made it broke away from the chassis on the second roll. In the other two cases the bars were bent well out of shape (there are no requirements for bar standards in pre-1960 cars). Nevertheless, the bars helped to prevent serious injury as they supported the weight of the car as it overturned. The human body can withstand a fair bit of punishment, but it won't support 1000kg of car upside down. That is why I have a roll bar in each of my cars - the benefits outweigh any 'perceived' risk.

samx5 wrote:I've been looking at the MX5 Plus bars, my interest is in structural rigidity for everyday driving and additional side impact strength, rather than for rollover protection. I'm more likely to get t-boned in the city than roll my car. In any case, the twin hoop bars will sit quite a bit higher than the seats on my NB8A, as the seats are not as tall as the NB8B seats pictured. I'm also 6 foot tall, so my head will be above the bar as well. The bars look very well made. Would like to have a closer look before purchasing, but I don't know of any cars with them fitted in SA?

Have a look at this thread for more details on the MX5 Plus roll bars: http://www.mx5cartalk.com/forum/viewtop ... 44&t=35960

hks_kansei's comments above, "Ignoring the driver's seat in this image, where it looks to be moved forward for a shorter driver, the bar sits at the same height as the passenger seat!" ARE quite accurate, the picture is of my car and I'm a "short-arse" I'm 5'10" and actually prefer to be slightly further forward than in the totally relaxed position when "driving with intent". When the seat is right back and bolt upright, the roll bar is only marginally taller than the seat.

MINX's comment are right on the money too - best single chassis stiffening mod short of a full roll-cage.

bigdog wrote:On the subject of being outside the bar's protection - I have personally watched three race cars roll (Winton, Amaroo and Oran Park) in historic racing, where the drivers were taller than the bar. In each case they walked away with minor cuts and bruising. In one case the bar was so poorly made it broke away from the chassis on the second roll. In the other two cases the bars were bent well out of shape (there are no requirements for bar standards in pre-1960 cars). Nevertheless, the bars helped to prevent serious injury as they supported the weight of the car as it overturned. The human body can withstand a fair bit of punishment, but it won't support 1000kg of car upside down. That is why I have a roll bar in each of my cars - the benefits outweigh any 'perceived' risk.

THANK YOU bd! I was waiting for this statement.
for you nay-sayers, in a rollover, do you really think that your body will remain rigid and in the exact same position as normal driving? No, the law of inertia states that it will lean and tuck into the car as it flips. Think about it.

I'm getting pretty sick of reading the same arguments for and against roll-bars every single time someone brings it up. If you want one, get one, if you dont' then don't dissuade people from getting one. Yeeesh!

Wiz, you might want to use the "search" function beforehand, this topic has been repeated adneauseum.... emphasis on neauseus

That was what I was meaning. They'll provide more protection than just your head. If you want them, go for it.