Run Flat Tyres

[Gorb]

Is it possible to swap the 18 inch run flat tyres on my UX for normal tyres in the hope that road noise is reduced?

I have Bridgestone Turanza tyres at the moment - are other run flats available and any quieter?

[ColinBarber]

I believe Lexus also use Dunlop runflat tyres which are quieter. Personally I think I will move to normal tyres and a can of goo when my wife's tyres need replacing.

[Bill Dawes]

My forthcoming UX Takumi will have run flat, anyone had a new UX recently with run flats and how are you getting on.

Bill D.

[Gorb]

I test drove a UX without run flats and it was a lot quieter. I got run flats as an upgrade that I didn't know about and thought at the time it was a good freebie. If you have a choice don't get them.

 

[Spock66]

19 minutes ago, Gorb said:

If you have a choice don't get them.

I've heard similar stories from BMW drivers, and if you do get a flat the tyre is usually toast whereas a conventional tyre can often be repaired for a modest cost.

[LenT]

13 hours ago, Gorb said:

Is it possible to swap the 18 inch run flat tyres on my UX for normal tyres in the hope that road noise is reduced?

I have Bridgestone Turanza tyres at the moment - are other run flats available and any quieter?

This question about ROF (Run On Flat) seems to have come up a lot recently.  The answer is that any ROF can be substituted by ‘normal’ tyres as they are not specific to the wheel.

The result will almost invariably be a better, quieter ride with even a possible improvement in fuel efficiency.

This is because the ROF uses a thicker, heavier, less flexible sidewall to enable it to support the vehicle in the event of a puncture.  Even then its speed and mileage is severely restricted.

The disadvantage is that road surface noise and imperfections are amplified by the reduced flexibility of the sidewalls. 

Many repairers - and even some makers - will not support a repair, should it even be possible, because the damage caused by the wheel rim running on the tyre carcass is unknown.

They were initially developed for heavy industrial use, especially for military vehicles.  It was believed, for example and with some justification, that if you’d suddenly had bullets deflate a tyre, then you might not be inclined to stop and replace the wheel - or even use an injectable goo kit.  

I don’t know much about the area in which you live, but unless you think this feature will be a real benefit, then I suggest you will be better off with, say, a set of the latest Michelin CrossClimates and - with all due respect to Colin - a suitable SpaceSaver wheel and no tyre inflation kit.

[Roger Bill]

Lexus have also fitted Dunlop run flats to the UX which are said to be quieter. Also the UX facelift due to enter production in August will apparently be fitted with a new Bridgestone run flat which Lexus say are quieter.

I recently had a puncture a few yards from home. I used a trolley jack to raise the car and an extension on a socket to remove the wheel. In my aged physical condition I doubt any scissor jack and wheel brace would have been sufficient. In 100,000s of miles of driving I've only suffered about half a dozen punctures but I remember one on the M6 and one at a busy set of traffic lights in the rush hour. Neither would have been repairable with tyre repair gunk. In both cases, changing the wheel was scary and these experiences are indelibly etched in my memory.

For these reasons I think I'll be prepared to suffer the extra noise and harder ride of run flats.

[LenT]

13 minutes ago, Roger Bill said:

I recently had a puncture a few yards from home. I used a trolley jack to raise the car and an extension on a socket to remove the wheel. In my aged physical condition I doubt any scissor jack and wheel brace would have been sufficient. In 100,000s of miles of driving I've only suffered about half a dozen punctures but I remember one on the M6 and one at a busy set of traffic lights in the rush hour. Neither would have been repairable with tyre repair gunk. In both cases, changing the wheel was scary and these experiences are indelibly etched in my memory.

For these reasons I think I'll be prepared to suffer the extra noise and harder ride of run flats.

I think this is a very reasonable point.  I’ve only had to use the SpaceSaver once, when a well-meaning passerby broke the valve clean off the wheel.

In my case changing the wheel was no problem at all, but then the car was safely off-road and I imagine an IS250 is a different proposition to a UX.

Tyres are a compromise anyway.  For example, greater grip is usually at the expense of mileage.  ROFs are a compromise of ride quality over the convenience of a limited but continued mobility in the rare event of a tyre deflating.

It has to be a personal choice!

[ColinBarber]

1 hour ago, Roger Bill said:

Lexus have also fitted Dunlop run flats to the UX which are said to be quieter. Also the UX facelift due to enter production in August will apparently be fitted with a new Bridgestone run flat which Lexus say are quieter.

I recently had a puncture a few yards from home. I used a trolley jack to raise the car and an extension on a socket to remove the wheel. In my aged physical condition I doubt any scissor jack and wheel brace would have been sufficient. In 100,000s of miles of driving I've only suffered about half a dozen punctures but I remember one on the M6 and one at a busy set of traffic lights in the rush hour. Neither would have been repairable with tyre repair gunk. In both cases, changing the wheel was scary and these experiences are indelibly etched in my memory.

For these reasons I think I'll be prepared to suffer the extra noise and harder ride of run flats.

Your vehicle comes with roadside assistance - just let them deal with a flat tyre if you are unlucky enough to get one.

[rayaans]

Yes it will reduce road noise amongst other benefits like a softer ride, less chance of buckling a rim if hitting a pothole and theoretically greater fuel efficiency due to less weight

Theyre usually cheaper to replace as well

[Roger Bill]

23 minutes ago, ColinBarber said:

Your vehicle comes with roadside assistance - just let them deal with a flat tyre if you are unlucky enough to get one.

In some cases I agree this would be a good option. But I wouldn't want to wait for them stuck at a busy set of lights in the rush hour so would possibly wreak an alloy wheel driving to a safe spot.

Amusingly a wealthy friend had his Porsche Cayenne breakdown in just such a location and had to wait an embarrassing hour for the AA to arrive. His previous 911 also cost him a lot in repairs and maintenance. I keep nudging him to consider something more reliable like a Lexus.

[Las Palmas]

Run Flat are excellent for driving around in war-zones and in extremely bad unpaved roads.

With Continental (not Run Flat) I did about 50K kilometres in Africa (MB350S) and never had a flat; mostly on unpaved roads with rocks etc. Not the most quiet tyre, but there it did not matter.

[rayaans]

2 hours ago, Roger Bill said:

In some cases I agree this would be a good option. But I wouldn't want to wait for them stuck at a busy set of lights in the rush hour so would possibly wreak an alloy wheel driving to a safe spot.

Amusingly a wealthy friend had his Porsche Cayenne breakdown in just such a location and had to wait an embarrassing hour for the AA to arrive. His previous 911 also cost him a lot in repairs and maintenance. I keep nudging him to consider something more reliable like a Lexus.

Same argument for run flats that everyone uses but the problem is that most would wait 30 mins to an hour for roadside assistance than constantly drive on rock hard, noisy tyres, sometimes for a year or two.

The risk of a puncture / catastrophic tyre event is really quite low in the grand scheme of things

[Roger Bill]

32 minutes ago, rayaans said:

Same argument for run flats that everyone uses but the problem is that most would wait 30 mins to an hour for roadside assistance than constantly drive on rock hard, noisy tyres, sometimes for a year or two.

The risk of a puncture / catastrophic tyre event is really quite low in the grand scheme of things

True, but look how many buy a sports version of cars which have rock hard suspension with low profile tyres when they rarely have the opportunity to drive on roads with bends and speed limits which go anywhere near conditions which would benefit from such suspension setups. Or those with large 4x4 who never venture offroad. It's all down to personal choice and your own particular order of priorities and which compromises you're prepared to live with. For me changing a wheel or waiting an hour on a motorway hard shoulder scares me sufficiently to want the "insurance" of runflats. In the same way I continue to line the pockets of car insurers after many years of accident free motoring (fingers crossed).

[rayaans]

1 hour ago, Roger Bill said:

True, but look how many buy a sports version of cars which have rock hard suspension with low profile tyres when they rarely have the opportunity to drive on roads with bends and speed limits which go anywhere near conditions which would benefit from such suspension setups. Or those with large 4x4 who never venture offroad. It's all down to personal choice and your own particular order of priorities and which compromises you're prepared to live with. For me changing a wheel or waiting an hour on a motorway hard shoulder scares me sufficiently to want the "insurance" of runflats. In the same way I continue to line the pockets of car insurers after many years of accident free motoring (fingers crossed).

Ive had a few cars with stiffer suspension and low profile tyres. Again, it doesnt really increase the risk of a puncture. My Jag had 20" wheels and the tyres were 30 profile. 

You cant really compare car insurance to run flats. One is compulsory, the other isnt

[Roger Bill]

1 hour ago, rayaans said:

Ive had a few cars with stiffer suspension and low profile tyres. Again, it doesnt really increase the risk of a puncture.

Sorry but the point I was trying to make is that many are happy to forego a comfortable and quiet ride everyday for the very occasional times they might be driving in conditions that would see any benefit of improved handling.

As to your point, there is quite a bit of evidence that low profile tyres are more prone to damage from pot holes and speed bumps. For example, see https://www.national.co.uk/blog/low-profile-tyres-the-complete-guide

3 hours ago, rayaans said:

You cant really compare car insurance to run flats. One is compulsory, the other isnt

Good point. I should have used house insurance which is optional as the example to illustrate my point that we're willing to spend significant amounts of money to guard against a rare event simply because if that event does occur it can be very expensive. There is a small risk of serious injury or damage to your car in stopping on a motorway hard shoulder hence the advice to leave the car and stand behind the crash barrier.

In all cases it's down to personal choice as to what risks and compromises you prefer.

[LenT]

33 minutes ago, Roger Bill said:

As to your point, there is quite a bit of evidence that low profile tyres are more prone to damage from pot holes and speed bumps. For example, see https://www.national.co.uk/blog/low-profile-tyres-the-complete-guide

 

Spot on there, Roger.  I can contribute personal evidence to the vulnerability of low profile tyres and alloy wheels to attack by potholes and kerbs - especially when they hide under snow!

I managed to mark both nearside wheels in my first week of ownership, driving around our country lanes which had never been a problem in my previous Honda Accord.

Given the choice, I would have had the Lexus with the optional 17” wheels and meatier tyres - and the promise of a more comfortable ride.  But I doubt I’ll bother to change them now.

[Gorb]

Thanks for the comments.

I think to sum up the differences between normal tyres and run flat tyres:

Normal tyres - Less noisy, more comfortable ride, better economy, possibly repair if punctured and cheaper to buy. No spare tyre with UX so would need roadside recovery or if repair goo used tyre would need to be replaced.

Run flats - Opposite of above but can drive with a puncture. Tyre would need replaced if run on flat.

[Gorb]

On 6/8/2022 at 7:12 AM, Roger Bill said:

Lexus have also fitted Dunlop run flats to the UX which are said to be quieter. Also the UX facelift due to enter production in August will apparently be fitted with a new Bridgestone run flat which Lexus say are quieter.

I recently had a puncture a few yards from home. I used a trolley jack to raise the car and an extension on a socket to remove the wheel. In my aged physical condition I doubt any scissor jack and wheel brace would have been sufficient. In 100,000s of miles of driving I've only suffered about half a dozen punctures but I remember one on the M6 and one at a busy set of traffic lights in the rush hour. Neither would have been repairable with tyre repair gunk. In both cases, changing the wheel was scary and these experiences are indelibly etched in my memory.

For these reasons I think I'll be prepared to suffer the extra noise and harder ride of run flats.

Can you provide a link to where Lexus discuss the noise levels from the Bridgestone (or any) tyres please?

[Roger Bill]

7 hours ago, Gorb said:

Can you provide a link to where Lexus discuss the noise levels from the Bridgestone (or any) tyres please?

For the tyre data check www.lexus.co.uk/new-cars/ux/build select a model grade, then customise, then the wheels tab and finally click "tyre info". Then you will get a dialog box containing tyre data as per the attached screenshot.

17" wheels on the 250H are fitted with non-runflats With tyre goo, 18" wheels fitted ro F Sport and Takumi have 18" wheels and run flats. The UX 300e fitted with both 17" and 18" are all fitted with non-runflats.

When I checked a couple of months ago both Bridgestone and Dunlop tyre data were listed for the 250h. Now only Bridgestones are shown. 300e 18" wheels are fitted with Michelin non-runflats their noise rating is 69dB vs 71dB for the Bridgestone runflats.

For slightly less detailed tyre data check websites like www.blackcircles.com/tyres/225-50-18?runflat=1&id=10229

[LenT]

14 hours ago, Gorb said:

 No spare tyre with UX so would need roadside recovery or if repair goo used tyre would need to be replaced.

Surely another option is a SpaceSaver wheel - unless there’s some peculiarity of the UX that prevents it?

There are circumstances - such as a rip in the sidewall or breakage of the valve (as happened to me) - where injecting goo will be ineffective or impossible.

A SpaceSaver has the same performance limitations as a Run Flat, but is lighter and more compact than a full size tyre and wheel.  It can also be legally used on either axle, even if different sized tyres are normally used - provided it is there to get the car to a tyre replacement service.

When I bought my Lexus I made a point of checking that just such a wheel was there.

[Gorb]

25 minutes ago, LenT said:

Surely another option is a SpaceSaver wheel - unless there’s some peculiarity of the UX that prevents it?

There are circumstances - such as a rip in the sidewall or breakage of the valve (as happened to me) - where injecting goo will be ineffective or impossible.

A SpaceSaver has the same performance limitations as a Run Flat, but is lighter and more compact than a full size tyre and wheel.  It can also be legally used on either axle, even if different sized tyres are normally used - provided it is there to get the car to a tyre replacement service.

When I bought my Lexus I made a point of checking that just such a wheel was there.

The boot is tiny and it isn't possible to easily fit a space saver tyre. I have already removed the false shelf to make a reasonable sized storage space.

[ColinBarber]

1 hour ago, LenT said:

Surely another option is a SpaceSaver wheel - unless there’s some peculiarity of the UX that prevents it?

You could struggle to fit a jack and wheel brace in a UX boot on your first attempt, let alone get a wheel in there 🤣

[LenT]

59 minutes ago, ColinBarber said:

You could struggle to fit a jack and wheel brace in a UX boot on your first attempt, let alone get a wheel in there 🤣

I apologise for my ignorance of the Lexus range. ☹️
I’m sure the UX has many other redeeming qualities, but that’s an unexpected lack of boot capacity.

As Gordon has already identified his preference for a quieter ride, I guess he’ll  have to accept the inflation kit/mobile phone options to cover the rare flat tyre eventuality.

I hesitate now to make any more suggestions (!) but I’m very happy with the performance and sound levels of my Goodyear Eagle F1 Asymmetric 5s.  They do do some sizes as Run Flats, but they also claim to have a noise reduction system that improves the level generated internally.

It would require more research!

[Rabbers]

On 6/8/2022 at 1:39 PM, Roger Bill said:

… For me changing a wheel or waiting an hour on a motorway hard shoulder scares me …

I completely agree with Roger.  You should go for runflats if, perhaps as the result of a nasty blowout or having had to wait for help in some god-forsaken place, you dread getting a puncture.  My own experience of runflats (Michelins) is limited to 9000km I did in one IS300h before I traded it in for another.  I briefly considered transferring them but then thought it silly to forgo the OEM normals (Bridgestones) on the new car.  On normal roads the runflats gave a decidedly firmer ride and jolts were especially more perceptible to passengers because they weren’t anticipating them.  They were also noisier, but not intolerably so.  However, on motorways and fast roads in general I felt hardly any difference, and I thought the car might even have been marginally more stable at high speeds.  I believe I would probably choose runflats as a matter of course if I did more motorway driving, particularly long-distance, which nowadays rarely exceeds 10% of my monthly total.