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Are rear roll bar stays needed
ste - 8/11/15 at 11:18 PM

As title, are they needed? On most roadsters they are mounted to the flimsiest part of the car at the very back. I'm thinking about not fitting them on mine, are they needed for IVA? Can't get to the manual at the minute as I'm on my phone. Thanks

loggyboy - 8/11/15 at 11:42 PM

No roll bar at all is needed for IVA. Only most msa events that require them (sprints etc).

Ben_Copeland - 9/11/15 at 06:06 AM

No point in fitting one at all if it doesn't have back stays, they should go down to the floor of the boot. Never liked them fitted to the top of the boot. Plus it makes fitting the back panel a pain

jeffw - 9/11/15 at 06:24 AM

Depends if you want a roll bar as decoration or something that could save your life. Without rear (or forward) stays it will simple collapse if any force was applied to it.

Bluemoon - 9/11/15 at 07:44 AM

quote:
Originally posted by jeffw
Depends if you want a roll bar as decoration or something that could save your life. Without rear (or forward) stays it will simple collapse if any force was applied to it.


I would agree but there are some photos of an MK Indy that rolled with standard hoop and rather surprisingly it didn't collapse.. Still if you don't want a chocolate teapot in for something this safety critical fit rear stays.

Dan

SteveRST - 9/11/15 at 09:44 AM

Pic NTDWM but it shows how a standard Westfield roll bar without rear stays faired. eeek.


gaz_gaz - 9/11/15 at 09:51 AM

If you only want it for hanging the washing on you can skip the back stays.
As a potential life saver it needs them.

jps - 9/11/15 at 02:53 PM

Out of interest - are there many known cases of 'standard' locosts being rolled / what the resultant damage was?

Not to suggest it's a pointless exercise doing a rear-hoop well - but I'd assume that a roll without a full rollcage will end fairly badly in any event?

jeffw - 9/11/15 at 04:02 PM

Depends on how high the ROPS (rollover protection) is. MSA require 5cm gap between your head and a line from the Rollbar to the strongest point on the front of the car (cam-cover probable in a fibreglass car).

Don't forget that these ROPS have issues with soft human skulls that are not protected by a helmet (imagine getting hit on the side of the head by a 45mm steel tube at 30MPH) and a full cage will likely break your arms in a rollover as they are likely to end up outside the cage. Always something to ruin your day.

jps - 9/11/15 at 04:37 PM

quote:
Originally posted by jeffw
5cm gap between your head and a line from the Rollbar to the strongest point on the front of the car (cam-cover probable in a fibreglass car).


Quite....!!!

Sam_68 - 9/11/15 at 04:54 PM

quote:
Originally posted by jps
Out of interest - are there many known cases of 'standard' locosts being rolled / what the resultant damage was?

Not to suggest it's a pointless exercise doing a rear-hoop well - but I'd assume that a roll without a full rollcage will end fairly badly in any event?


It's not common.

Possibly worth musing on the fact that well over half a million MX5's, MGF's etc. have been built without rollover protection, yet civilisation as we know it has, so far, survived. You can be assured that if the streets were littered with dead hairdressers the insurance companies, if not government, would have done something about it by now.

That's not to say that you shouldn't design a roll bar to be suitably strong, with stays and diagonal at least, if you choose to have one, but the statistical risk of not having one, or having one that is little better than cosmetic, is certainly quite small.

I share Jeff's concerns about full cages for anything other than competition use. I'd go so far as to suggest that they are incompatible with road use unless you're wearing a helmet and are tightly strapped in with a full harness, otherwise they probably worsen risk rather than improve it.

But you gotta die of something, and there are worse ways than a sharp blow to the head with a big lump of steel - as many hundreds of trout and sea bass of my (brief) acquaintance would hopefully attest.

Neville Jones - 9/11/15 at 06:24 PM

You not been to a race meeting for MX5's have you Sam? They fall over with great regularity, and very easily. Saw one go over at an autosolo recently as well.

Go to a Catervan meeting too, same thing.

Proper ROPS are there for good reason, and don't anyone get talked out of putting at least a decent rollover bar, diagonal, and backstays. It doesn't take much of a bump on the side to get tipped over.

If you want to pop your empty head like a balloon Sam, that's your prerogative, just don't belittle anyone who choses to be sensible and safe.

But hang on, you don't have a 7 type car, and never built one either.

Cheers,
Nev.





[Edited on 9/11/15 by Neville Jones]

Sam_68 - 9/11/15 at 06:48 PM

quote:
Originally posted by Neville Jones
You not been to a race meeting for MX5's have you Sam?

...Engineers don't gamble or bluff, so don't try me


We're not talking about racing, Nev.

With racing, you have to comply with the Blue Book, period.

...which as of next year will mean full roll bar to RAC spec. with diagonal and backstays as a minimum.

The risks in road use are quite different, and considerably lower, particularly if you don't drive like a mindless idiot (in which case a sharp dose of Darwinism would probably be in everyone's best interests).

Who do you think designed the MX5, without a rollover bar, if not engineers?

I appreciate you think you're a lot cleverer than the combined resource of a corporation like Mazda, but they obviously came to a different conclusion about the risks involved.

Sam_68 - 9/11/15 at 07:35 PM

Nev's trolling aside, in fairness I guess I should explain why I'm against the degree of risk aversion that seems to be becoming so much more prevalent in recent years.


The RAC is enforcing changes that will make a lot of existing cars non-compliant for speed events next year, by making an MSA spec. roll bar mandatory instead of recommended for Specialist Production Cars. Now, that's a change that you may or may not agree with; on the one hand, it will certainly make things a little safer, and it might be argued that if you can't afford the highest levels of safety on your competition car, then you shouldn't be competing... on the other, it risks driving some cars (and competitors) out of the sport due to the cost of implementation, and there's very little evidence that the reduced standard in place at the moment has actually caused a significant increase in injuries, in a sport in which serious injuries and fatalities are thankfully now very rare.



But more importantly, with regard to road cars...

Scaremongering (and it is just that) about the risks involved in kit and specialist cars is not in our own best interests, as an industry or as enthusiasts.

We've seen SVA/IVA introduced with little, if any, measurable improvement in accident safety (kit cars were an exceptionally good insurance risk before and they remain so - and the insurance companies know better than anyone the liabilities involved), but adding a substantial element of cost and bureaucracy that has almost killed the UK industry.

It would be a very small step - easily implemented within the existing regulations - to introduce increased safety requirements that would kill home-built cars, stone dead, forever, as they already are in many other European countries.

It comes down to this:

BE CAREFUL WHAT YOU WISH FOR.

Neville Jones - 9/11/15 at 07:50 PM

Ahhh, 'Sam' old chap, same shite, different dunny.

I've never seen an MX5 rolled on the road, but know it's happened too often. The guy I buy parts off has a number of stories.

The racecars is another matter entirely. Same with 7 types, though there are enough pics of accidents involving these on the road, that any person driving one, and without some sort of roll protection, is just simply a fool. Put the hat on if it fits 'Sam' .

It is grossly irresponsible to suggest that any sort of crash protection is unnecessary, and a proper rollover bar with backstays, to MSA specs, would be the minimum for a Locost type vehicle.

Pop your own head like a teenagers zit, but don't encourage anyone else to do the same.

You're not an engineer 'Sam', so stop trying to act like one.

For someone who started life as a 'technician', draftsman by any other name, you're far too arrogant. So, quit the garbage and word turning. You're the troll, with your unending argumentative pedantic posts.

Cheers,
Nev.

And for what it's worth, I'd like to see an Australian type rego system here, where a proper signatory engineer has to sign off that the car is safe, just like planes, but with none of the draconian rules.

If an Aus system was in place here, the general standard of kits would be magnitudes higher, and tough luck if the dross disappears, just like it did in the early 90's. Stoneleigh used to fill every shed and pavilion, now a small percentage, but the standards are mostly much higher.

[Edited on 9/11/15 by Neville Jones]

steve m - 9/11/15 at 07:56 PM

Am the only one who finds the above two children bickering, a little bit irritating

Getting to the stage of ruining a perfectly good forum

i dont give a flying poo who is right, or who is wrong, and doubt anyone else cares, so please, both of you go back to playing with Lego,

As it seems both are about 13 years old

steve

Neville Jones - 9/11/15 at 08:02 PM

Sorry Steve, I won't reply to this clown any further.

BenB - 9/11/15 at 08:09 PM

Awww Steve, why did you have to say that- I've just ordered a fricking family size delivery of popcorn and everything!!!!

Sam_68 - 9/11/15 at 08:48 PM

I'll be polite.

quote:
Originally posted by Neville Jones
And for what it's worth, I'd like to see an Australian type rego system here, where a proper signatory engineer has to sign off that the car is safe, just like planes, but with none of the draconian rules.

If an Aus system was in place here, the general standard of kits would be magnitudes higher, and tough luck if the dross disappears, just like it did in the early 90's. Stoneleigh used to fill every shed and pavilion, now a small percentage, but the standards are mostly much higher.


Sadly, that's not a likely outcome - and I haven't seen much evidence over on the Ozzclubbies forum that the majority of their members, who live with the system, would necessarily agree with you - including the most prominent of their signatory engineers.

More likely that the amateur built exemption would disappear altogether, and LVTA would become much stricter, requiring much more investment and testing to get a car into production.... driving costs up, because that testing has to be amortised over small production volumes.

Since you mention planes, I'm sure you're aware that the UK system for homebuilt aircraft effectively precludes any UK designs being certified, with a Catch 22 clause that says you've got to demonstrate that a design is safe by operational use, but you're not allowed to operationally use it until its been demonstrated as safe... as a result we've got a negligible industry for homebuilt aircraft, whereas we could have a bouyant and thriving one.

You've made it clear that you favour a much smaller, more strictly regulated industry; that's your prerogative.

I regret the passing of the pre-IVA days when, yes, there was some awful dross about, but also a lot more innovation, imagination, and choice, in a much more vibrant industry; I'm realistic that we'll never see such a relaxed legislative regime return, but I'd prefer that things didn't get any more bureaucratic or expensive than they are already. I'm entitled to my view, even if you don't like it?

I'll leave it to others to decide for themselves which attitude best fits the ethos of this particular forum.

steve m - 10/11/15 at 12:10 AM

I take it Sam, the hint didn't work ?

Your negativity to criticism is now getting rather boring

you are blocking and reducing a fantastic forum, for other much worthy people than your egotistic , vain self, to the extent, that some followers to the forum, and far far superior to you, will leave, and not post

If you like Aus so much, then wee off to the convict isle, and do us all a favour

steve

mark chandler - 10/11/15 at 07:20 AM

And back to the original question, are they needed for IVA, No! But then neither is the hoop so you can scratch the whole thing off your list.

Is it wise to have no protection, car manufacturers spend millions on roll over protection, things that pop up on big springs etc to keep the lines of the car true, some do not bother.

My car's roll bar cost £90, 2" CDS, local place added a couple of bends and I mounted as per the MSA and a nice person popped around and certified the car for sprinting.

My life is worth more than saving £90, the car was tracked for 8 years before I started to sprint it, the bar was part of my original design although certified only 2 years ago.

A full cage is a different matter, for a road car it's probally more dangerous as you may not be strapped in to the same degree when it's required, so put a value on your life and do the right thing.

ste - 10/11/15 at 07:27 AM

Money has absolutely no bearing on the decision. I see lots of cars that have roll over hoops only and just wondered if just the hoop is adequate. Obviously it isn't from the above pictures. I already have the steel to make them and one of my concerns was the aesthetics too as I want to keep the rear cover one piece which isn't possible with angled rear stays as the are wider at the bottom so will not go through simple holes.

Thanks for all the replies so far, certainly food for thought there

Sam_68 - 10/11/15 at 09:50 AM

quote:
Originally posted by ste
Money has absolutely no bearing on the decision.


Yes, obviously when you're actually manufacturing the roll bar, the difference in cost between a fully braced hoop and a simple one is trivial - I should clarify that the concern with the changes to Blue Book rules for speed events is the cost of replacing a roll hoop on an existing car.

Is there any possibility of angling only the top part of the stays, so that the bottom parts are parallel and run down through holes in a one-piece cover, with a horizontal tie (and possibly diagonal) above the level of the cover, to mitigate the effect of the kink?

Or make the stays separate, with a reamed bolted fixing to the main roll hoop?

russbost - 10/11/15 at 10:21 AM

Op's Q was "Are rear roll bar stays needed"

To be able to answer the Q you first need to know in what context.

Many, many years ago I built & raced an autocross Mini, I built & welded a "cage" into the car (which had the whole roof panel cut away for added lightness & replaced with thin fibreglass skin) which was made from exhaust tubing (yes, really, the RAC weren't so picky in those days), it was light, as was the car, & speeds on a muddy field are relatively low, I welded it together with 2 x 12V car batteries, some jump leads & an arc welding stick holder! (I was 16 when I built it, 17 when I raced - put it down to no money & youthful exuberance) IIRC it DID have to have a CDS centre hoop, but that was the only "proper" roll protection in there. Last meeting of the season I rolled the car on on of the quickest parts of the circuit, the shell was a bit rotten in some fairly structural areas & to a large extent came apart - all except for the roll cage & the floorpan it was securely attached to! I walked away with just a heavily damaged ego! Moral of the story? If properly designed it doesn't have to be that strong or heavy in its individual parts.

The Westfield pictured seems to have quite a thin section to the roll hoop, you will note the rear screen is also sitting in the boot & the seat belt is no longer attached to the drivers side, I can't see the drivers head anywhere, nor loads of blood, so have to guess he was very adept at ducking - would I want to be in a car designed that way - heck, no.

However, would I like to be in a car with a full cage, diagonals, stays etc. without a crash helmet - also, heck no - see Nigel Mansell for details, he tried making substantial contact with an MSA approved roll hoop wearing a state of the art, best money can buy, crash helmet - as I recall he got away with concussion, had he not been wearing a helmet I would expect him to be very dead.

If a car goes side over side then a roll hoop such as that on the Westy pictured, might, just might, hold up sufficiently to give some protection, however with even just a thin supporting stay each side & a single, relatively flimsy diagonal it would do a 10 x better job. In a roll where it makes contact with the ground in a forward or rearward motion then without stays it is indeed the chocolate teapot or fireguard.

So, I guess the answer is "horses for courses" - it depends what use you're going to put the car to, how fast you intend travelling on what sort of roads, how good a driver you are & what sort of risk you find acceptable, at the end of the day, if you are just plain unlucky & in the wrong place at the wrong time, you could be doing 10mph & everything right, it won't stop a truck from crushing you, but you could say the same about walking on the pavement! - don't quite know why anyone is quoting the RAC bluebook as it has no bearing on road use unless you are planning on rallying & I'd hardly class that as normal road use. Bear in mind that if you rear end something & submarine under it then you're probably going to be decapitated anyway, roll hoop or not, only a full cage with frontal impact section is going to protect you from that, however if that happens without a cage, I assure you, you won't be worrying about it! Even with no protection at all, it's probably still safer than a motorbike!

Neville Jones - 10/11/15 at 10:31 AM

quote:
Originally posted by steve m
I take it Sam, the hint didn't work ?

Your negativity to criticism is now getting rather boring

you are blocking and reducing a fantastic forum, for other much worthy people than your egotistic , vain self, to the extent, that some followers to the forum, and far far superior to you, will leave, and not post

If you like Aus so much, then wee off to the convict isle, and do us all a favour

steve


Don't send the clown to Aus!!!!

I'd like to spend my UK winters there when I get old enough to slow down. There's a nice place called Hastings Point in north nsw, where I spent my childhood.

There's good reason he got the bums rush from the Oz site, from what I'm told. And it's much the same situation as here. But why did he go to that forum to start with?

Cheers,
Nev.

Sam_68 - 10/11/15 at 10:52 AM

quote:
Originally posted by russbost...don't quite know why anyone is quoting the RAC bluebook as it has no bearing on road use...


Also possibly worth mentioning that the 'standard' Blue Book solutions are a universal, 'one size fits all' approach, applicable where specific calculations and certification have not been undertaken, and as such are overkill for very lightweight cars.

Where companies have gone to the trouble of properly designing and separately certifying ROPs for their cars, it usually proves very easy to achieve compliance with alternative designs and/or reduced tube sizes.

I guess the relevance of Blue Book is that it at least gives you a reasonably well-considered benchmark to work to (albeit designed to work in conjunction with helmets and harnesses), whereas IVA regs. offer none?

Sam_68 - 10/11/15 at 11:15 AM

quote:
Originally posted by Neville Jones
There's good reason he got the bums rush from the Oz site


Still at it, Nev?

Point of fact, old chap, but I didn't get the 'bums rush' from the Oz site at all: I still post (I did so only yesterday) and get on very well with almost everyone there.

The only two people I don't get on with are your 'friend' Rod, and his sidekick Trevor (Noble), and I'm not alone there... Noble is universally hated as a cantankerous old troll, and Rod not far behind, given the large number of supportive messages I've received.

But you've already admitted that you're deliberately trolling me on behalf of Rod (if, indeed, you're not one and the same - your style and attitudes are identical), as an attempt to carry over his - and only his - personal vendetta from another forum.

Rod has admitted that he and his cronies (presumably including yourself) have deliberately trolled this forum in the past; under the user name of Syd Bridge, I think he mentioned?

Please quit: I'm sure it's as tiresome for other members of this forum as it is for me. If you want to make an issue of something I posted on the Ozclubbies forum, then at least have the courage to do it on the Ozclubbies forum, instead of inflicting what you obviously see as a personal crusade upon others on an unrelated forum who really don't give a f***.

loggyboy - 10/11/15 at 11:50 AM

What a funking trolling mess of a thread!

the op was 'ARE BACKSTAYS REQUIRED FOR IVA'

Which was answered in the first reply. END OF.



[Edited on 10-11-15 by loggyboy]

Irony - 10/11/15 at 12:21 PM

Are we not getting to the bit where they start posting up their CV's and claiming to be the pinnacle of engineering excellence?

Mr Whippy - 10/11/15 at 12:44 PM

I wonder if Sam_68 is infact CaLviNx?

I would recommend you fit backstays after the IVA as a roll over is a stupid thing to die for and it's quite easy and cheap to fit them though you'll have to take the back panel off so maybe make it easy enough to remove and I wouldn't weld over the fuel tank either.

I have a very strong roll bar over my soft top landrover otherwise I'd would never let my kids in it, just not worth the risk.

Neville Jones - 10/11/15 at 04:34 PM

He could well be, but for the fact C went to Cypress or somewhere like that, didn't he?

I'm not Syd Bridge, never have been nor will be. I joined the group after two left and went back to aus. So you're barking up the wrong tree there, 'Sam'.

I've been accused of being someone I'm not, but, Sam, tell us you're not

Martin S####t, of Berkeley, Gloucs? Just like your Photobucket and Linkedin accounts say? I've got the screen shots to prove it.

You don't like getting back some of what you hand out, do you?

Cut out the nastiness and bully boy stuff when someone disagrees with you, and try and be nice. And stop posting reworded stuff you've read elsewhere on the 'net, to make it appear as though it's your own. We're not all fools you know.

Cheers,
Nev

Mr Whippy - 10/11/15 at 06:37 PM

quote:
Originally posted by Neville Jones

He could well be, but for the fact C went to Cypress or somewhere like that, didn't he?



Maybe he got banned from there too

Sam_68 - 10/11/15 at 07:30 PM

Nev,

What's your point?

I've never made any secret of the fact that my main career is architecture; I've made numerous posts on it here and on other forums. See the recent topic on here about airfields being classified as brownfield land, for a start. In fact, I'm pretty sure you'd have found reference to it on the thread I linked on my first ever post on Ozclubbies, if you cared to look.

Is it any of this of any relevance to this thread?

[Edited on 10/11/15 by Sam_68]

TheGiantTribble - 10/11/15 at 09:04 PM

Re Are rear roll bar stays needed

IMHO if you are going to fit roll bars, you might as well fit ones that are going to be of use, after all you don't want to be finding yourself halfway through an accident thinking 'oh crap I wish I'd bothered to fit them' . And yes it's amazing what goes through your mind when you are having an accident.

Re the chest thumping

Open a new thread where those who want to argue who knows more, whose understanding of metals/physics/chemistry/turnips and the mathematics of flight of Santa's' reindeer, can argue to your hearts content. Or at least one of you emerges staggering from the smoke and ashes victorious. God knows the rest of us will be long dead and buried by then.