Hi

Looking at a new company car. BMW 520D M Sport tourer is number one choice, however, read many times that run flats give a harsh ride, I’m a high mileage driver am I better off on normal tyres?

Can I change to normal tyres on the run flat rims?

If I choose run flats do the winter tyres need to be run flat as well?

Thanks

Yes you can run normal tyres, you used to just need to opt for the ‘extra load’ (XL) version of the tyre.

Will have no impact on your insurance, but a courtesy call to your insurer to check it is not an issue is advised

You need to run all 4 tyres the same, either all normal or all run flat. Why would it matter between summers and winters? Only issue is having a compressor and tyre sealant in the boot for when running normal tyres.

I have always found normal tyres to give a much better ride and better grip than runflats, but I believe the newest generation of runflats are much improved, so it might not be necessary to switch to them these days

Maybe. Yes. No.

<span style=”font-size: 0.8rem;”>Newer RFTs are better than older ones, but I’d still go normal over RFTs for comfort. </span>

Ssying that, avoiding the larger wheel option will make more difference. Dropped from 17” RFT to 16” regular tyre setup on my car and a huge difference.

As it’s M sport it is likely to be harsh, but try it out.

Ive always swapped mine (2 minis, and a 120) but might be worse on small cars with small profile tyres. On a big car with decent seats it might not be too bad.

The real M cars use normal tyres I think.

https://singletrackworld.com/forum/topic/car-tyres-sorry-anyone-on-run-flat-winters/

i have just swapped from a 220 gran tourer with ‘luxury’ spec and normal tyres to an m sport one with run flats and larger wheels. The m sport is noticeably harder riding and less smooth, but this could be as much to do with the suspension and larger wheels as the run flats.  The seats in the luxury were more comfortable too.

I did however hit a plank of wood in the road with the ‘normal’ tyres, which instantly flatted the rear tyre. This was not repairable with the little sealant pack and resulted in >3 hours waiting for the AA to take me to a garage for a tyre. For avoiding that pain, the run flats may be worth having!

F31 320d Sport with normals here.   Lovely smooth drive.

I swapped out the wife’s mainly because of cost of the tyre..run flats were alot more expensive so given how few flats I’ve had in 30 years of driving the risk is worth it. It’s a car we use as a local run-around anyway so if we did puncture we wouldn’t be too far from home and have breakdown cover for puncture recovery. There are a couple of cans of tyre weld in the boot, but I wouldn’t want to rely on that stuff, but if it works then all’s good.

It was a slightly better ride on normals and less road noise.

Swapped my runflats on my 130i for regular tyres and the comfort and grip is much improved.

I’ve stuck a spare wheel and jack in the boot. Don’t fancy my chances with Sealant

I’m going to go against the consensus and say the run flats on an M Sport is fine and comfy although that is with the adaptive suspension. It gets noticeably harder in sport mode but that’s just for the back roads. I was coming from a Focus ST and the missus has a Golf R so perhaps I’m comparing it to much harsher riding cars.

I’ve got runflats on my Nan series, they’re fine, much comfier than some cars I’ve had with normal tyres.

I was going to swap to non runflats the other week when the fronts needed doing, but the Mrs drives it most and it saves waiting for the breakdown people on her own if it went pop.

My F31 320d M Sport xDrive came with hateful 19″ runflats.

It was a much nicer drive on 18″ non run flat winters. Just keep the same on all corners.

How often do you get a puncture?

Obviously there is matey boy up there who drove into a static object, but in all my miles I’ve only ever punctured once. Stick with normal tyres.

I swapped. Runflats have very stiff sidewalls which on bmw wheels often lead to cracks in the alloy wheels. After I experienced this issue twice I’ve got new non-bmw wheels and also carry a spare on longer journeys.

Swapping to non rft made a big difference to the ride quality, and less road noise.

Thanks for the replies, have test drive next week, may opt for the SE model if too harsh

I have a 320i Sport (not M Sport) on 18s with Runflats. I have no problem at all with the ride or comfort.

I have had two punctures in the last year, so it was great to be able to carry on driving and then drive it down to the tyre place to get it sorted. I’ve never fancied my luck with tyre sealant, and I work with someone who had a puncture and the sealant wouldn’t have solved the issue, so he had a long wait for someone to come.

I have 19in run-flats on my 2017 SE touring. Bought it off the showroom floor so didn’t have the option to swap them. Less harsh than the equivalent 18s on the Sport. That was a non adaptive setup tho.

I’ve got used to them.  I’d prefer a set of 18s with non RF tyres, but not enough to pay a shed load of money for them.

F31 onwards are fine in run flats.

Depends what you want from a car too. No point getting stiffer suspension and then putting crappy soft tyres on it.

Ive tried various tyres, all run flats some made a some improvement in comfort over potholes, but then you loose the poise and control of a more sporty tyre.

Run flats on modern BM’s are not bad

Actually putting compliant tyres on stiff suspension often improves handling and grip on normal roads. When suspension moves when the body rolls, the geometry of the suspension tends to roll the wheel up on an edge, so if you have stiff walled square edged tyres you roll the tyre up on its edge reducing the contact patch and grip, if you have softer more compliant tyres the tyre sidewall deforms and maintains a larger contact patch onto the road and a higher level of grip.

And then of course you’ve got road noise which is noisier on stiffer walled tyres and the ability of the car to soak up those crashy bumps like hitting pot holes and square edges which will transmit more harshly with stiff walled tyres. In fact i’m really struggling to think of a real benefit of stiff walled low profile tyres at all on normal cars on normal roads for normal driving. They ride worse, they grip less, they’re noisier, they’re more expensive their extra weight means your suspension isn’t working as well due to higher unsprung weight, you’re emissions and fuel economy is worse.

Run flats on modern BM’s are not that bad…better than they were, probably not an issue at all with the very expensive adaptive suspension option box ticked, but still not as nice a normal tyres.

Having said that if you get the run flat option then the car will come with tyre pressure sensors as you cannot use runflats without them, if you go for the non-run flat option then it might not come with tyre pressure sensors, so maybe go for the run-flats, see how you get on with them then you always have the option to swap them out later.

I also found that runflats were more susceptible to punctures than normal tyres. I assume the extra stiffness means objects penetrate rather than the rubber deforming.

Doesn’t the M135/140 come with a choice of runflat or non-runflat pilot super-sports?

I’ve owned 530d sport tourings in the past, after the first 25k on runflats I changed to non runflats for the remaining mileage (240k)

I just used to buy the car new, run it until the tyres needed replacement then change to normal tyres thereafter.

Have to say that the normal tyres were markedly quieter.

Alan – You’re right the standard tyre from factory on an M135i is the Michelin Pilot Super Sport. I’m not sure about the M140i but when I bought (got in a load of debt) mine in 2015 there was no option offered for RFT’s. When the Michelins were worn I ended up changing to Eagle F1’s and I prefer them – I think you lose a bit of ultimate performance in the dry but they seem quieter and better in the wet, so all round an improvement.

OP – as above, I would give it a whirl and see what you think. My wifes 320i M-Sport+ on 19″ RFT’s on non-adaptive suspension isn’t noticeably more crashy/harsh/loud than the M135i on 18″ non-RFT’s but then again there’s lots of other variables at play (e.g. better soundproofing on a 3 saloon than a 1 hatch).