Runflat Tyres (or Tires!)

Here's a couple more rants while we're at it! Even if you have a spare tire, the jacks and wrenches the automakers give you to change them are a joke. Look like they were intended only for a flat, level, pristene roadway to set on, and look about as sturdy as kitchen utensils.

Another thing that irks me is that on some pickup trucks, the spare tire cranks down from the underside of the bed with a cheesy pully mechanism. Well, where I am in Rustbelt USA, the stupid thing will get wet, dirty, and will seize rock solid. Stranded!

You're point is rock-solid in that automakers will go to any lengths to slip you cheap, lightweight, and downright unsafe details. Not a good thing to count on when you're stranded in the middle of nowhere!

Pickup jacks are cheesy. Somewhere alongside the road, is a jack buried up to the pad in the dirt. And, no matter how frozen the spare letdown cable is, someone will manage to steal your spare.

Think CAFE, in the US anyway. Most of these new "innovations" are designed to reduce the weight of the vehicle and improve the mileage. I am not in agreement with all of what the auto makers have done either. My vehicle doesn't even have a spare tire, why you ask?? Because it has an air compressor and hose to connect to the valve stem. Fat lot of good that does with a blow out. But, that seems to satisfy what the "standards" are.

Cars are now drive by wire with more than 20 million lines of code. They sure don't go through all the hoops that aircraft do, but yet they are very similar in design and carry a lot more people in total. Got a problem, plug it into the diagnostic computer and change a module. Great for the repair guys, but hard on the pocket book.

All these new "gimmicks" (with the additional sensors required) may make some people feel more as ease behind the wheel, but I think that we are losing the skills of actually having to be a driver as we had to do in the old days.

Ebay is an excellent source for replacing the "donut" spare by finding a rim/tire combination that matches your other 4 wheels. Comes in extra handy when you include it in your tire rotation regimen, you'll get 20% more wear out of all your tires, which may even offset the extra cost.

"Space saver spares" were introduced during a rubber shortage or tire recall as I recall.

They are much cheaper for the automakers who could care less about their customers after the car leaves the dealer's lot.

While I agree with you that the manufacturers save money, it was my understanding that the tiny spares were utilized to meet government mileage requirements.

As for the "space saver" spares, I recall seeing them appear in the 60's "ponycars".

Wife had a '67 Firebird - wonderful car, but no trunk space unless you were transporting ping-pong balls. Even with the space saver, there was hardly any trunk room.

Four for all!

Why would anyone complain about a run-flat tire if it gets you 50 miles?

Are you saying you actually prefer to pull over on some unsafe section of road at 2AM in the morning and put on a space saver spare?

If you expecting perfection you won't find it on this planet.

Getting 50 miles is OK if your destination is nearer than that, but otherwise you might as well sit on the side of the road where you got the puncture - till when?

I'd pull over to somewhere safe (or as safe as possible) and fit my full-size spare. Agreed it's a pain but it wouldn't be the first time I'd done it. I do my own maintenance and repair but I accept that not everybody is that way inclined. Those who can't change a wheel (eg most women) can call their breakdown company.

I don't expect perfection but I think the modern alternatives to a traditional spare wheel are going further away from perfection, not towards it.

Have you opened the links in Andy G's #10? The 2nd one specially doesn't fill with confidence about run-flats.

That's your choice, but I would keep driving until I got somewhere favorable.

50 miles or less is more than 95% of my driving. for someone like me it's not likely to be a problem

As far as tire performance goes I would not use them, but for someone that doesn't care about high performance like some mom, it may be extra insurance worth the tradeoff.

Some years ago, Car and Driver Magazine did a series of tests with a Corvette, using the "space-saver" spare tire at each of the four corners of the automobile. The car was put through their testing regimen, with braking, acceleration, and roadholding/turning tests. Much to everyone's surprise, there was very little difference in performance between the stock Goodyear "Gatorback" tires and the tiny spare, although it did look funny.

Was that the April 1st issue?

I dislike "Runflat" tyres completely, at least the BMW versions that I have experienced.

Further to the valid points already made here, they are often un-repairable after being holed in some way it would seem. Luckily, I have never had a hole in one....

That means theoretically you could have a brand new car and tyres and 10 miles down the road, get a hole in one and you need a brand new tyre again (assuming it blows almost in front of the tyre store!!), because its not repairable for some reason.....

I find them also noisy and bumpy too.....but always seem to drive worn RF tyres on a pickup, so I am a bit negatively biased maybe!! People do not fit new tyres just to sell a car that often!!

Runflat tyres need to be replaced far earlier than normal tyres as once they are down to under half the tread and you are a fast driver (legal US/UK/most of Europe OTHER than Germany, drivers need not read further as I am talking about WAY over any legal limit where you live), and are often above 100MPH, then the part RF worn tyres have some disturbing characteristics that you need to know about, the slightest "join" or unevenness in the road surface of what should be just a high speed Autobahn corner, will cause the car to severely "snake".

You could "suddenly" leave the road completely... The first time it happened to me, I assumed it was a bad road surface, but after it happened several times on the same drive (a matchstick appears to be enough to cause it!), I mentioned it to the owner and he immediately said "Sorry, I forgot to mention, part worn Runflat tyres are bad news!"

Tkanks Buddy!!

He replaces all RF tyres, no matter how old, with conventional ones and adds a sealer cartridge to the car!!! He does not like having to replace 4 RF tyres due to them being part worn and unsafe, for an angry customer....

Braking even slightly is a "no no" on high speed corners with worn tyres.....only do it if you have no other choice....

New RF tyres will let you drive at any speed you wish, the same as normal tyres.....no problems with high speed cornering or braking.

BMW have made changes to the suspension geometry over the last 5 years or so, which have improved matters greatly, but to my mind not enogh. But I have not tried one of the very latest models.....to be certain.

Luckily there is a really good fix, you simply buy normal tyres of the correct size and type and your car will be perfect!! Though you now have the problem of no spare......

I also dislike the other possibilities of sealer etc.. But for RF BMWs I would make an exception if a spare wheel cannot be stowed!!

I drive a lot of different cars for a friend, picking them up and delivering them all over Europe and if its a BMW with RF tyres, that have done some miles, I drive slowly!!! Never over 100MPH.

Looking on the web I found this, which fits in well with my personal knowledge and experience:-

Information on "Runflat" tyres

You will even find the following there which I fully agree with as well:-

Why change from run flat to conventional tyres?

We are not recommending that you change the type of tyre your vehicle was originally supplied with. Changing to normal tyres could affect the handling of your car, so you must always consult the manufacturer before making this type of change.
However, some people choose to do this for the following reasons:

• Conventional tyres are generally cheaper than run flat tyres and have better availability
• Some drivers find that conventional tyres give a smoother, less bumpy ride than run flat tyres
• In line with most leading tyre retailers, National will not repair a run flat tyre following a puncture

That is the same here, no tyre company will repair any RF tyre that has been holed......also these tyres are usually not cheap to replace either.....sometimes twice the price of good conventional tyres.....

I see no "pluses" for Runflat tyres....

I found this, it personally gave me even less nice thoughts about them, but they were brand new tyres, which do then appear to work as designed, though VERY noisy.....

we-put-bmw-run-flat-tires-test-what-you-need-know

Enjoy!!

Plenty of good points there. Your first link is where I got my quote about 30 mph for 50 miles, but your BMW link, and most of the correspondence in it, confirms my view. The annoying thing IMHO, is that there has been an acceptable solution from the start of the motoring age - a proper spare wheel. It's a problem which need not exist if manufacturers applied "if it ain't broke don't fix it". Space-saver spare and aerosol give a weight and cost saving, but as your post shows, this doesn't apply to run-flat, specially end-user cost.

While I'm ranting, another thing being foisted on a mostly unwilling motoring public is the electric handbrake. I've heard the theory that is also for cost saving, but I find it hard to swallow. More a case of increased income from repair bills, which I believe is > £1000 for electric vs about £150 for conventional. Also OK while working properly, but fail-safe, so any problem the brake applies and it's a wheels-up tow job. Before somebody tells me, I realise it's not a new idea, some cars had them decades ago (Jaguar, 1950s?) but went back to mechanical. A bit like the column change fashion.

And why (rhetorical question) is it often referred to as an "electronic" handbrake? What's electronic about it? Electric, electromagnetic or electromechanical maybe, but not electronic.

Good post of yours, particularly about the electronic handbrake, I thought it was just me that did not like them.....

So, if one has run-flat tires and gets a puncture, how does one know that they have said puncture?

I would think there's enough change in the driving characteristics that you'd know. There's something about noise etc in Andy G's links.

I expect you're right about driving characteristics and I also imagine many vehicles might even have an audible alarm if a tire loses some air pressure.

It was mostly just an idle question.

Personally, I'd never have a vehicle with run-flat tires.

Punctures are almost unheard of where we drive.

Besides, my wife insists that we have AAA. They change them for us.

OK thanks Lyn, I thought maybe your post was a bit tongue-in-cheek

You know, they are almost as uncontrollable as a flat normal tyre, one corner goes down just the same, and you get a computer warning too...only a paralytic drunk would not notice!!!

"only a paralytic drunk would not notice!!!"

I'll bet that the paralytic drunk suddenly looks like he is driving better, too.

LOL!!

Could be!!!