Run Flats or Not Run Flats

WesthillDave · Post by **WesthillDave** » Wed May 10, 2023 5:54 pm

Hi
I once put a pair of new rear tyres on a 911, different manufacturer than the fronts, but with a lovely tread pattern! The car was terrible to drive, wouldn`t drive in a straight line and always correcting, cornering no better.
Changed the fronts to the same manufacturer and tread pattern...perfect!
My own E89 has four Michelin Pilot Sport tyres and it is a delight to drive. Dead straight, hands off, and corners on rails! A firm but comfortable drive. Hope this helps.

N4LLY · Post by **N4LLY** » Wed May 10, 2023 6:42 pm

I ran run flats to the point of MOT failure, so had quit some time with disapointment re handling, tram lining, harshness etc.

The swop to michealin PS4's was an immediate transformation and most excellent

Just my experience.

IanzZ4 · Post by **IanzZ4** » Wed May 10, 2023 8:15 pm

Thanks everyone. Please keep the opinions coming. There’s a picture developing here and it’s not looking good for the current tyre setup!

As I said earlier I’m going to have a top down (pardon the pun) check by the Indy BMW workshop Monday. If that shows all good then it’s off to Black Circles to buy a set of standard Michelin ps5 boots. £576 to deliver the fun the car promises to give over the next few years is acceptable.

Will post results next week.

Best regards

Ian

Pondrew · Post by **Pondrew** » Wed May 10, 2023 8:29 pm

IanzZ4 wrote: ↑Wed May 10, 2023 8:15 pm £576 to deliver the fun for car promises to give over the next few years is acceptable.

Will post results next week.

Best regards

Ian

When you get it sorted, you will find they are really good little cars to drive.

Busterboo · Post by **Busterboo** » Thu May 11, 2023 10:17 am

It occurred to me the week I bought my Z4 six and a half years ago that the E89 would have been commercially more successful if (1) BMW hadn't put silly numbers on it - not least my 35is that's 3 litres and not 3.5 - and (2) had put decent tyres on it and not the Bridgestone runflats that scared me when they tramlined the first time I drove the car at speed.

Did nobody at the factory ever have to describe the models to a journalist? Was there no feedback from authorised dealers? And did BMW never test-drive the cars it was making?

Strange, really.

sars · Post by **sars** » Thu May 11, 2023 11:06 am

When I test drove the e89 in 2010, I very nearly didn't buy one because the test car had 19" alloys and RFT and it really was an appalling combination of road noise and jittery drive. In the end I opted for the standard square 17" with 225/45R17 RFT and the ride and handling was great. After the first winter, I relegated the 17" wheels to winter tyres and plumbed for a set of BBS alloys, again with a square 18" with 225/40R18 Goodyear Eagle F1's and the ride was similar.

RMB · Post by **RMB** » Thu May 11, 2023 8:54 pm

I test drove a 35i on standard fit runflats once, and never again. It was awful. Tramlining, harsh ride etc etc. Plus it kills the wheels.

Had an E82 on REO50 runflats and ditched them for MPS4 and it absolutely transformed the car plus significantly cheaper too!

This is a no brainer.

Jembo · Post by **Jembo** » Thu May 11, 2023 9:12 pm

Imagine u paid quite a few £ 000’s for your fancy.

Considering just 4 modest patches of rubber keep it away from the scrapyard, am sure the best suggestion made by 99% of the above for premium rubber has to be the one you start with.

The cost of new premium rubber will probably also be a lot less than you’ll loose dealing with the aftermath of an undervalued insurance claim & their subsequent years extra premium getting back what they forked out

Pondrew · Post by **Pondrew** » Thu May 11, 2023 9:21 pm

Jembo wrote: ↑Thu May 11, 2023 9:12 pm The cost of new premium rubber will probably also be a lot less than you’ll loose dealing with the aftermath of an undervalued insurance claim & their subsequent years extra premium getting back what they forked out

Non runflats are a 'modification' as far as insurance is concerned. If you don't inform them they won't pay a penny.

I can't find any evidence of 'cheap' or runflat tyres contributing to any accidents in the UK. The 'ditch finders' phrase is common on car forums due purely to 'tyre snobbery' IMHO.

Jembo · Post by **Jembo** » Thu May 11, 2023 9:29 pm

Pondrew wrote: ↑Thu May 11, 2023 9:21 pm
Jembo wrote: ↑Thu May 11, 2023 9:12 pm The cost of new premium rubber will probably also be a lot less than you’ll loose dealing with the aftermath of an undervalued insurance claim & their subsequent years extra premium getting back what they forked out
Non runflats are a 'modification' as far as insurance is concerned. If you don't inform them they won't pay a penny.

Depends which Ins Company

When I asked LV on my old 3.0, had it confirmed in writing provided were all same type, a decent brand & good tread, NRF’s wouldn’t be an issue.

Same went for using winter tyres - not an issue provided using BMW alloys available on the model

What handler said they didn’t like was mixtures & ditchers (cheap poo on a performance car), that’s when they got picky.

OP’s got a rare old mix

Pondrew · Post by **Pondrew** » Thu May 11, 2023 9:32 pm

Jembo wrote: ↑Thu May 11, 2023 9:29 pm What handler said they didn’t like was mixtures & ditchers (cheap poo on a performance car), that’s when they got picky.

So are you saying that LV ask what brand of tyre you have on your car?
I have three cars insured with LV. I don't remember that conversation with them, or anyone TBH

Jembo · Post by **Jembo** » Thu May 11, 2023 10:05 pm

Pondrew wrote: ↑Thu May 11, 2023 9:32 pm
Jembo wrote: ↑Thu May 11, 2023 9:29 pm What handler said they didn’t like was mixtures & ditchers (cheap poo on a performance car), that’s when they got picky.
So are you saying that LV ask what brand of tyre you have on your car?
I have three cars insured with LV. I don't remember that conversation with them, or anyone TBH

No

The chat was about mixing different tyres, especially cheap ones

Whether I could run NFT & Winters with BMW alloys was in writing

javis20 · Post by **javis20** » Fri May 12, 2023 2:11 pm

I once had a problem like that. Turned out to be a defective tire. Pulled cord or something.

IanzZ4 · Post by **IanzZ4** » Fri May 12, 2023 8:56 pm

Again thanks to you all for sharing your experiences. Still looking like a new set of premium brand tyres is going to be the remedy. Looking forward to hearing the results of the inspection Monday. Will share it with you all, probably from the tyre shop waiting room

Ditch finders - that takes me back to my RS2000 days

Have a good weekend all.

Jasonn · Post by **Jasonn** » Sun May 14, 2023 6:45 pm

Just my two penneth, I had those god awful Bridgestones on mine - got the dealer to replace the ones on the front with brand new ones as they looked a little too worn. Drove it home and was terrified on the M25 with the behaviour - went to my trusty mechanic, nothing untoward noticed on the ramps other than 'f**king nice little motor there' from him.

Resigned myself to the handling, but heard a lot about the RFTs - swapped them out for Goodyear Eagle Assymetric 5,got a blinding deal from Formula 1 autocentres - they had a "we'll beat anyones' price" offer - so I played them off against the others and then downloaded some vouchers before getting to the checkout.

As regards insurance, I've renewed it three times, none of the companies have objected to the car having non-RFTs, but I got them to confirm it in writing/email and no cost implication either.

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