[Dream Weaver]

Took the Civic down to National Tyres today for some new fronts. I've used this branch for years and they always do a price match so they came back with £180 fitted for 2 Turanza's - a like for like replacement for what was already fitted from new.

Got home tonight and on checking the tyres they have the RFT run flat logo on the side.

Is it safe to run these without a warning system? I will speak to them tomorrow but they may just say it's safe to use them and I want to be sure in case they try and wriggle out of it.

All the numbers check out - 205/55/R16 91V ER300 but the Turanza's have another 2 letters which can be FZ, HZ, LZ, YZ etc - not sure what this is but we did have HZ and these are LZ.

I did say I wanted no RFT tyres when ordering them but they must not have noticed when fitting them.

 

[angie4m]

I've noticed that Bridgestone seem to be advertising in TG mag that their tyres are run flat and safer for everyone to use.

I think they are cashing in on the fact that lots and lots of cars now come without spare wheels and this is an answer from the likes of BMW etc. There is no harm in running them without a warning system but you may find that the ride of the car gets a bit harsher than you maybe expected.

 

[Pottsy]

Self-Supporting


Self-supporting tyres feature a stiffer internal construction, which is capable of temporarily carrying the weight of the vehicle, even after the tyre has lost all air pressure. To provide "self-supporting" capability, these tyres typically attach rubber inserts next to or between layers of heat-resistant cord in their sidewalls to help prevent breaking the reinforcing cords in the event of loss of air pressure. They also feature specialized beads that allow the tyre to firmly grip current Original Equipment and aftermarket wheels even in the event of air loss. Because self-supporting tyres are so good at masking the traditional loss-of-air symptoms that accompany a flat tyre, they require a tyre pressure monitoring system to alert the driver that they have lost air pressure. Without such a system, the driver may not notice underinflation and may inadvertently cause additional tyre damage by failing to inflate or repair the tyre at the first opportunity. Typically, self-supporting tyres maintain vehicle mobility for 50 miles at speeds up to 55 mph.


Examples: Bridgestone RFT (Run Flat tyre), Dunlop DSST (Dunlop Self-Supporting Technology), Firestone RFT (Run Flat tyre), Goodyear EMT (Extended Mobility Technology), Kumho XRP, Michelin ZP (Zero Pressure), Pirelli RFT (Run Flat Technology) and Yokohama Run Flat.

I'd take them back!!

 

[Pottsy]

And from Bridgestone:

Bridgestone United Kingdom

Bridgestone strongly recommend to only fit RFT on a vehicle that is originally equipped with run flat tyres (either standard or as option). Vehicles fitting Run Flat Tyres (standard or optional) must always be equipped with a tyre pressure warning system.

 

[HappyMan]

I'm with Pottsy on this one - Take them back!

 

[angie4m]

Thanks Pottsy This is something that they are also failing to advise in their advertisments and I wonder how many tyre fitters are fully aware of this?

 

[allan40alt]

I'd take them back!!

Yes, you could find the handling compromised with the fronts only being run-flats. Could be dangerous if hard braking is required, especially if the road is wet or damp.

 

[Pottsy]

Allan - I think the real issue is that when they are punctured and are in run-flat mode, you have only 50 miles at up to 55 mph max. With no TPMS you have no idea you have a puncture and could potentially drive for hundreds (or thousands) of miles at high speeds with a tyre that can't do that. And may fail horribly!

 

[Pottsy]

Thanks Pottsy This is something that they are also failing to advise in their advertisments and I wonder how many tyre fitters are fully aware of this?

They should be aware - I'm going to guess that this was a dumb mistake, especially since the run-flats are more expensive!

 

[angie4m]

They should be aware - I'm going to guess that this was a dumb mistake, especially since the run-flats are more expensive!

Hopefully it was

 

[allan40alt]

Allan - I think the real issue is that when they are punctured and are in run-flat mode, you have only 50 miles at up to 55 mph max. With no TPMS you have no idea you have a puncture and could potentially drive for hundreds (or thousands) of miles at high speeds with a tyre that can't do that. And may fail horribly!

Dead right. I had 'run-flats' on my Mini Cooper S Works and you had to programme into the computer the tyre pressures; any drop in pressure would sound a warning. Hard ride as well (mind you, I guess the Works suspension didn't help!).

 

[Jack The Lad.]

Porkies, Porkies and more Porkies from the adverts.
Good job Honda don't tell them.

 

[alanwalne]

Do RFT's need a special rim or ridge akin to tyron bands to stop the tyre separating from the wheel when there is no pressure to hold them on?

 

[HappyMan]

They should be aware - I'm going to guess that this was a dumb mistake, especially since the run-flats are more expensive!

I would suspect you are right!

 

[Dimplyred]

Do RFT's need a special rim or ridge akin to tyron bands to stop the tyre separating from the wheel when there is no pressure to hold them on?

No the way they work is the side walls are a lot stiffer than on normal tyres and so with any resulting drop in pressure they are still able to support the weight of the car.

As a few people have said they shouldn't be fitted to a car that is not equipped with a monitoring system to inform the driver that one has lost pressure. Another way is the system monitors the speed of rotation of the wheels and if one loses pressure the overall diameter of the wheel and tyre decreases slightly and so rotates faster than the others, this is detected and the driver is alerted.

So yes take them back.

 

[Dream Weaver]

Thanks all, will call them tomorrow and arrange replacement.

Ironically, I'm sure I noticed in the sun the other day that the Civic dash does have a RFT warning light in the top right hand corner just right of the main computer display and I was wondering if it worked!!

 

[Kremmen]

The other thing is that they are 'run flat' because they have an extremely rigid tyre wall.

The ride must be considerably firmer compared to normal tyres ?

 

[Unknownsoldier]

Do RFT's need a special rim or ridge akin to tyron bands to stop the tyre separating from the wheel when there is no pressure to hold them on?

Yes, some are even strapped to the tyres to stop them coming off, run-flats should only be used on wheels which have the rims for them.

Tom

 

[illegalhunter]

Runflats are such a pain in the @rse , its like driving on soggy cornflakes.

 

[Pottsy]

I very recently had a long test drive in a new 320d. I commented to the salesman that at least it didn't have those wretched run-flats, like the 5 series, so the handling remained intact. After we stopped, he invited me to have a look at the tyres...