• The development of any software program, including, but not limited to, training a machine learning or artificial intelligence (AI) system, is prohibited using the contents and materials on this website.

What are the disadvantages of 'run flat tires'?

SL65

SL65

Ambitious but rubbish!
Joined
Jul 12, 2004
Messages
9,325
Location
Sydney, Australia
Car(s)
1998 Subaru Legacy 2.5L
I'm doing a report at school and it covers those run flat tires...
I wanted to know what are some of the bad stuff associated with them? I hear that the one's fitted on BMW's produce a lot of road noise but thats it.

Thought i'd ask the experts (you :) )
 
Expensive ;)
If you have to change it you can damage more things, sensors, processor units etc)
I heard that they are less comfortable, but can't really say because I haven't compared.
But I think it has to do with the reinforced sidewalls, so they don't have the springeffect that normal tyres have.
And they're heavier too. (about 20% maybe less now)
 
depends, you have 2 sort of run flat tires

tires which can run flat, and their disadvantages are the things josty said
or tires where a plastic band is wrapped around the rim, and when the tire is flat, your drive on the plastic band.
these have a metal wire running in the tire, which needs to be stretched around the rim, so it wouldn't come of when turning. makes the tires more expensive, and you need special equipment to mount them to the rim
 
Ok interesting, thanks guys :) Will use that
Continue to add if you got anything ;)
 
They're just for lazy people who don't like to be bothered to change it to their spare.
Seriously though, they protect the driver from losing control after a random tyre blowout. Tiff did a segment about them on a Fifth Gear episode. Perhaps somebody can fill in on the exact episode.

They aren't meant to be driven normally after they are punctured. They have the exact same function as a temporary spare. You should only drive on it until you can get it fixed. However, Tiff had no problem driving a car with punctured run-flats like the way he always does.

I also read that they have a stiffer sidewall, which translates to a rougher ride. It also means less sidewall flex; this can mean lower tyre roll and less predictable handling.

I personally think it's not worth the money. Obviously, car nuts like us take care of our tyres and maintains them properly . . . right? It's more for the normal folks who can't tell the difference between a nut and a bolt.
 
Bah save your reduced ride quality and drive around with the car equivalent of this stuff.

lrg_7887.jpg
 
Yeah it's right about re-enforced sidewalls giving a harsher ride.

Also... There's a chance drivers might not realise they've got a puncture.
 
My mini has runflats (cooper s) but I've never driven a mini without them so I can't really compare. Other owners do say that switching to standard tyres makes the ride more comfortable. I don't really mind it as is though, and I rather like not having a spare taking up space (not sure where they would find to hide one anyways!)
 
I really don't like car manufactures fitting run flat tires instead of a proper spare. I don't care how much weight it saves, that's just taking things too far. If trunk save is the issue, design a bigger trunk.
 
Leppy said:
Dark_Templer_102 said:
http://www.bmw.co.za/products/runflat/how.asp
http://www.etyres.co.uk/run-flat-tyres

Seems Audi and Lexus is joining the bandwagon
Read it and weep (did i spell that right)
Click to expand...

I don't know about Bihus... but I was taking the piss.
Click to expand...

I was too. ;) but he probably was just messing with me because I have an Audi avatar and previously had a Lexus sig. :)
 
rotational mass is critical to acceleration, braking, turning, MPG etc... so it's important to keep the mass of a wheel+tire as low as possible and as close to the center of the rotating mass as possible. Run flat tires add a lot of weight to the outside area (tire). The other downside is cost.
 
theblue said:
rotational mass is critical to acceleration, braking, turning, MPG etc... so it's important to keep the mass of a wheel+tire as low as possible and as close to the center of the rotating mass as possible. Run flat tires add a lot of weight to the outside area (tire). The other downside is cost.
Click to expand...

Don't some run flats have a hard centre band that is closer to the inner radius of the wheel?
 
You must log in or register to reply here.
Top