Run Flats to Standard Tyres

Jokaty82

I have a question. I have done a lot of reading up about this but just wanted some further view points.

I have a mini cooper which has run flats - they are useless tyres except for obviously their main purpose of running on a flat.

They hardly last at all, I don't do many miles yet seem to change my tyres often, more often than on any other previous car. They are also £95 quid a pop (ouch!).

I have read on many forums about people changing their run flats to standard tyres. They recommend carrying Holts Tyre stuff and compressor. Just in case. Due to the fact minis have no where for a spare.

I am considering doing this next time they are all low. My tyre man recommended changing all 4 at a time, or if could not afford front together then back together. He said lots of people do this as run flats dont last long.

Boyfriend threw up question though about MOT. He thought it was the law that all cars had to have spare tyres or run flats or it would fail MOT/be breaking law.

Can someone let me know whether this is true and there view points on this. Thanks

daveyjp

No need to have a spare for an MOT.

Smarts, Honda Jazz and Insight don't have them and don't use runflats.

If you change to ordinary tryes just check any breakdown cover you have covers you for attending a car without a spare wheel - some don't.

MrsTinks

I never found I got much less milage out of them to be fair when I had my Cooper... And I drove it like it should be driven (just bording on what is legal and what ain't )
Personally I found they had good grip and didn't do much less milage than another good brand of tyre. If you want grip though the you get less milage, if you want milage over grip then choose a harder compound tyre...

vikingaero

When I had a Cooper with run flats, I changed to normal tyres and bought the foam insert, mini compressor and bottle of gunk for about £65.

DaveMacD

There are a few cars on the market now that only have a bottle of tyre weld in the boot. Just bear in mind that tyre weld won't work on large tears or sidewall punctures, so putting it down a pot hole will likely require a call out of a mobile fitter. There is also a speed limit for driving on it as well. It's not perfect, but if you really want rid of the run flats, you don't really have much choice.

AdrianHi

There is no MOT issue here at all.

I spend time on a BMW forum where this subjects discussed a lot, I tend to be one of the bigger contributers on such discussions and have been throught the run flats to standard tyres tranisition (and back again as it happens) on my 3 series.
Do not run the car on a mixture of standard and run flat tyres regardless of what any mechanic or tyre fitter tells you. These guys don't neccesarily know it all. A run flat tyre responds very differently to a standard tyres on the road (you know that already from the harsh ride ) in anything but normal sedate driving. You need 4 tyres that respond the same way to make sure the car remains balance in harder cornering moves and emergency stops.

As for the dealing with a puncture solution Continetal Conti ComfortKit is good, tyre gel and compressor.
I used something that used to be called Ultraseal, now known as PunctureSafe and from personal experience I can tell you it is very effective so long as the puncture is not over 7mm. I got a 50mm cut in a tyre and this sealant still kept me moving for about 24 hours until it gave in.
You pre-treat the tyres with it, so if you get a puncture it keeps you going (just like a run flat) and permanently seals it if within the size limit. Just check your tyres occasionally for nails and screw and pull them / unscrew them out if you get any.

mark5

I ditched runflats on my Mini Cooper for normal tyres but still spend roughly £90 per tyre, I done it to improve the ride quality not to save money I still put Goodyear Excellence 195/45x16 on it.
I found I only got maybe 9000 miles from the front runflat tyres but then the rears went on forever maybe 30,000+ miles which evens out the cost.
The rears were only replaced when I went to no non runflats still with plenty of tread left on them.
I've been told by a few ppl on Mini Forums that its not safe to have a mixture of runflats and normal tyres on the same car.

Jokaty82

Thanks all, so if get done will get all 4 done at the same time. Am not really car-techie at all, hence why on here despite reading pages and pages of information!

The reason I would change is down to money, to be honest I like my car, treat it well and look after it but I am no expert, would I know how its supposed to feel?! Not sure. If the car had come with standard tyres would I have felt the difference? Again I dont know. I just feel like I am constantly changing my tyres, and the tracking is not out!

AdrianHi

Jokaty82 wrote: »

Thanks all, so if get done will get all 4 done at the same time. Am not really car-techie at all, hence why on here despite reading pages and pages of information!

The reason I would change is down to money, to be honest I like my car, treat it well and look after it but I am no expert, would I know how its supposed to feel?! Not sure. If the car had come with standard tyres would I have felt the difference? Again I dont know. I just feel like I am constantly changing my tyres, and the tracking is not out!

Rapid eneven wear, especial front tyre outer edges is partly a run flat tyre trait for some brands. If you do short trips the tyre never gets warm and as the tyre warms the pressure increases a little. The specified tyre pressure on cars account for this. A run flat tyre too low in pressure also results in faster outide edge wear. It is even more important with a run flat to check and correct pressures every 2 to 4 weeks to keep them right. Pressure too low and it starts to ride on the stiff sidewall causing tram lining, harsher ride and excessive wear.

When you change to standard tyres post back here and tell us if you think the car feels different when you've done at least 100 miles... I think you will notice.

Exhibit A, run flat tyre after 9000 miles, front wheel outside edge wear, the car had perfect trackign and alignment settings:


Exhibit B, rear wheel normal wear:


The brand of run flat tyre I have on now is lasting very well with no uneven wear after coming up 20,000 miles. Michelin Pilot Primacy HP ZP. It's a useless tyre on snow and slush though

Jokaty82

It shouldnt be for awhile as I have just changed one of the front ones and the other 3 are ok at moment, so hopefully they will all wear evenly and I can change all at the same time.

Would you say standard tyres makes the drive and handling worse then????

I do check tyres regularly, the warning light comes on quite often and do check them when this is on, but I could get in a habit of checking them even more often than that.

AdrianHi

Jokaty82 wrote: »

Would you say standard tyres makes the drive and handling worse then????

Different but I wouldn't say worse, I'd say better. The difference also depends on what car we are talking about. The heavier the car the more likely you are to notice a slight increase in body roll round corners as the run flat tyre doesn't have much give or flex in it compared to a standard tyres. I've felt this on my 3 series with standard suspension, people describe the same on their 5 series. Either of those cars with stiffer sports suspension or the smaller lighter 1 series and you don't notice this. So a Mini should be fine.

Traits I associate with run flat tyres are tram-lining (the car steers itself a bit - follows ruts in the road), harsh ride, possibly more road noise and grip insecurity on bumpy road surfaces. All these effects tend to be worse in cold weather as the tyre is less supple ni the cold. Put standard tyres on and these effects are removed or at least greatly reduced.
BMW are getting better at tuning suspension on cars for run flats, the latest models out of the factory are much better, mines over 4 years old now.