Run Flat Fitting

[pensioner]

When we bought our van there was an advert for a "gadget" that fits inside the wheel to prevent the tyre coming off the rim in the event of a puncture.
In the Army we called them runflats hence the heading, it was a large heavy rubber ring the fitted in the well of the wheel to stop the rim dropping into it, the gadget advertised seemed to be some sort of metal rather than rubber, but the cost was around £120 fitted.
Apart from the possible mess, what is wrong with using the sealer that is injected through the valve and will ooze out through any puncture hole, and will stop further deflation untill a repair can be done.
I have this in the tyres of my trike as carrying a spare wheel isn't an option.

 

[RogerL]

They're called Tyron Bands and cover the rim well as you describe.

Tyre sealants only work for slow punctures - Tyrons will keep the deflated tyre on the rim longer than without giving you time to stop - a blow-out is terminal.

I imagine that caravan road tyres are far more fragile than tyres on military vehicles/trailers - for obvious reasons.

Tyrons are a good idea - but I've never bothered having them fitted - make of that as you will.

 

[RayS]

It's all a question of luck / risk. In nearly 50 years of caravanning I have suffered only one blowout on a caravan. This happened at a reasonable speed (50 mph) and the two year old tyre stayed together so the Tyron bands (if I had fitted them) would not have improved the situation. There was no way a sealant would have solved the split sidewall. Fortunately, I did have a spare wheel ( fitted by the maker with a uni-directional tyre and - you've guessed it - it was the wrong hand but fitted and run 100 miles nevertheless)

Now in my dotage I insist on having a full, bi directional spare for the caravan and another similar for the towcar. Then I know that any roadside assistance will be able to fit as required and I can get to the next campsite.

 

[ProfJohnL]

There has been a long debate about the use of tyre bands. The fact is the manufacture has never provided conclusive evidence to prove thy do work on normal domestic vehicles. The use of such devices on military vehicles may have some benefit because of the dangers of projectile weapons, but unless you are touring in a military theatre ( or some inner city ghettos ) you are not likely to encounter such risks.

The use of the instant repair systems using aerosol canisters is only a get you to the nearest tyre depot for normal punctures, but they have no capability to make a tyre survive a blow out. Using some of these instant repair canisters contaminates the tyre and prevents conventional repairs from being carried out. There is a system which does help prevent punctures from deflating tyres, and still allows the tyre to be subsequently repaired, check with your tyre depot.

Most blow outs are caused by continued use of a partially deflated tyre which weakens the tyre wall. None of these systems will prevent damage to a tyre in the event of a blow out.

 

[Raywood]

We did have one caravan fitted with Tyron bands but as we never had a puncture cannot say if they work. They have been going a long time though and if they did not work then surely someone would have produced evidence to show that by now. As to whether they justify the cost this is a matter of personal opinion and you just have to decide for yourself if you think the cost is worth it for what may not be a very great risk.

 

[ProfJohnL]

...........They have been going a long time though and if they did not work then surely someone would have produced evidence to show that by now. .......

Hello Ray,

Unfortunately, (and not specifically related to tyre bands) advertising material has to meet some criteria set out by the advertising standards, but only a limited area (for example such as medicines, and where claims of compliance with standards) require there to be positive evidence of compliance.

This mens for a wide area of subjects advertisers have considerable freedom to make claims that are hard to pin down. For example there has been an increasing tendency in television advertising to claim a product is "up to 100%" effective - what does that tell us? absolutely nothing about how effective a product is, and in fact its conceivable it may totally ineffective yet the advertising is still accurate and legal.

In the case of tyre bands, they may be effective at what the manufacturer claims, but you need to look to see if the claims are actually relevant to your intended usage. The circumstances of usage where a tyre band may be effective are rarely the circumstances a caravanner would find themselves in.

Again with your background in insurance, I an sure you would find examples of where if a product can radically reduce the risk of a claim, the industry encourages its customers to use the product. (for example Insurance standard locks)

The product has been around long enough now to mature and be well understood by the industry. I did a trawl of the www a couple of years ago and from memory I only found three manufacturers world wide. I would have expected many more to be producing similar products if they were as good as they like to make you think.

Also look at the tyre and car industry, they are constantly trying to improve safety, So why is it these industries are not jumping up and down trying to get customers to use tyre bands? I am certain the answer is there is no positive evidence the use of these products is either beneficial or cost effective.

In particular, the named manufacture has been invited to publish factual evidence of the benefits of tyre bands, but has not done so.

I can find no secure evidence the use of tyre bands produces any significant safety advantage to normal caravanners. Equally though, there is no safety disadvantage, except that it makes changing a tyre more difficult and some tyre shops cannot handle wheels with tyre bands fitted. I believe there is more benefit from looking after your tyres and ensuring they properly inflated and in good condition.

So whilst there's nothing wrong with fitting tyre bands, if you need a sense of security the thats fine, but is it worth it?, then its more difficult to justify. If you feel the need to fit them to your caravan, then surely you should also have then fitted to your car!.

So from the lack of evidence and applying my own thought processes to the nature of the issues I conclude there is no positive case to encourage the fitting of tyre bands to caravans. It falls into the same category as crystal filled dehumidifiers for caravans, and compressed spring nose weight gauges, where clever marketing plays on a fear but ends up selling you something that in practice does very little reduce the actual risk.

 

[RogerL]

With things like this, the evidence is sparse
- some fit them but never have a tyre issue so never find out
- some others don't fit them but also never have a tyre issue so never find out
- some fit them, have a blow-out and the tyre bead stays on the rim
- some others don't fit them, have a blow-out and the tyre bead stays on the rim so never find out

- some don't fit them, have a blow-out, caravan gets wrecked but we can never find out if the same would have happened with Tyrons.

There is a hard-nosed view I tend to agree with - if it made a difference then insurers would charge more without them - but they don't.

 

[Gozza]

When I started caravanning, one of the questions on the insurance proposal was "Do you have Tyrons" - that was the C&CC scheme, can't remember who the actual insurer was. I didn't and I can't remember if I paid any extra as a result. I've not been asked since as far as I can remember.

I had three new tyres a couple of years ago (2 x road wheels, and the spare) and was going to get Tyron's fitted, but my local tyre specialist (part of a large national chain who claim on their website to be Tyron distributors) had never heard of them - unfortunately he only told me this after he'd fitted the tyres and I never got round to going elsewhere to get them done. One of many reasons why I'll never use that national chain again.

I was taught, as a novice caravanner, that Tyrons were a good thing and any responsible caravanner should aspire to them, but I've seen no evidence one way or the other to support this.

(for clarity, the fact that I refer to a national tyre chain does NOT mean I'm referring to National Tyre and Rescue!)

 

[ProfJohnL]

.........I was taught, as a novice caravanner, that Tyrons were a good thing and any responsible caravanner should aspire to them, ........................

Who was the teacher?

 

[Raywood]

I have seen no proof they work but at the same time none to say they don't. Not sure why no one has tried to prove this one way or the other by now but you lose very little by fitting them so I suppose it is a matter of trust if you take them. At the end of the day you just have to look at the cost and decide if the possible safety advantage is worth it for you.

 

[ProfJohnL]

........... Not sure why no one has tried to prove this one way or the other by now but you lose very little by fitting them so I suppose it is a matter of trust if you take them. ........................

Ray,

Surely you have been a forum member for long enough now to have seen the previous threads on these bands. A number of us have tried to get the manufacturers to justify their reasons for trying to sell these bands to caravanners, and as far as I am aware they have not responded in private or public.

You would have hoped that as these are being sold as devises to improve safety, the manufacturers would have been prepared to be more than ready to show hard scientific evidence to support their product.

Its de-je-vue, Just like the lack of clarity and ownership of how the 85% towing guidance value was established, the band manufacturers are not prepared to explain how their product is proven.

I'm always keen to see good safety advice being given or products promoted, but for advice to 'good' it must be open to public scrutiny. When no supporting evidence is provided the validity must be called into question.

 

[JohnMW]

The latest gimmick is the run flat tyre that has stiffened side-walls and I'm told the car manufacturer is not even supplying a can of air and mush. Mmmm sounds like the world is going crackers - what are they thinking. The caravan club insurers told me they would charge more if I did not carry a spare when going continental.
I have issues with the run flat of this type - everyone knows that tyres are the last contact with mother earth that transmits all the control features of the vehicle and every one knows that the tyre works by providing slip angles in varying degrees front and rear and during braking and acceleration - mess with the tyres at your peril.