G31/G30 - 20 inch change to non run flat?

[March2008]

Has anyone put non run flats, such as a Michelin 4s on? And noticed an improvement in ride?

I find the ride pretty good on run flats 75% of the time, but it has this busy feeling through the car that just feels out of place on some roads. Hard to explain, it absorbs pot holes and big bumps fine, but more of a general chatter through the car.

Any thoughts? The car is mechanically perfect I understand. 18 months old.

Just wondering if changing to non run flats will help. Car is on standard M Sport suspension

Thanks

[Ru99er]

I have a G31 on Msport suspension that came with the standard 18inch alloys, with Pirelli RF on, very comfy and wafty, recently put some non run flats on some 20inch alloys and the ride is only marginally firmer than the 18s, which I am suprised about. Purely down to the non RF on the 20s.

[V8 Animal]

I put a set of GY F1 none runflats on my X5 yesterday.
My drive home was pleasant 125 miles, will have to see how they fare.

[March2008]

Thanks, I’m gonna try the non run flats, it had a full set of new Goodyear F1 Run Flats put on by BMW before I picked up. So might have to take off, and sell or store them.

[Billy_Whizzzz]

Fed up with 20s cracking on my G31 (with adaptive) I’ve gone to non rf 18s. At the moment it is like night and day.

[Stillstand]

I use non-RFT Vredestein Ultra Vortis on my 20" wheels - ride is better than with RFT (M Sport suspension).

I use 18" winters too, which are even better again.

Edited by Stillstand on Thursday 31st October 14:02

[Billy_Whizzzz]

Stillstand said:

I used non-RFT Vredestein Ultra Vortis on my 20" wheels - ride is better than with RFT (M Sport suspension).

I use 18" winters too, which are even better again.

Can you get the Vredesteins in staggered 275/30/20 and 245/35/20?

[Stillstand]

Billy_Whizzzz said:

Stillstand said:

I used non-RFT Vredestein Ultra Vortis on my 20" wheels - ride is better than with RFT (M Sport suspension).

I use 18" winters too, which are even better again.

Can you get the Vredesteins in staggered 275/30/20 and 245/35/20?

Certainly can - those are the exact sizes I'm running. I know they're an unusual size to get a full set match. Some people change to 285 and 255 for more options. Not tried this myself though.

Edited by Stillstand on Thursday 31st October 14:03

[March2008]

Thoughts on the Vredstein? Wearing ok? Ride grip etc OK? Compared to the Goodyear F1 Run flat.

One thing I like about the F1, it has excellent Rim protection! Not tested yet, but you never know when you might catch them. Kerbing an alloy for me is a life changing event! 😂

[Stillstand]

I've done about 10k on the Vredestiens over two summers. I bough them as an alternative to Michelin PS4 that I used to run on my F31, but they were 3-400 a set more in the sizes for the G31 and I didn't want to run non-standard tyre sizes.

They've been solid so far - had no issues. Comfort is good, wear seems normal and grip doesn't seem worse than PS4s. I would say the noise is slightly louder than Michelin but honestly it's hard to tell without a back to back and because they're 20's, they have a large footprint in any case.

Rim protection is also decent, i've hit a few kerbs side on in multistory car parks and got away without any rim damage, so must work.

I believe the rolling resistance on the Vredesteins isn't as good as the others. I notice a 5mpg change between summer and winter tyres (they're obviously narrower too).

But for the price, no complaints.

[danb79]

Stillstand said:

I've done about 10k on the Vredestiens over two summers. I bough them as an alternative to Michelin PS4 that I used to run on my F31, but they were 3-400 a set more in the sizes for the G31 and I didn't want to run non-standard tyre sizes.

They've been solid so far - had no issues. Comfort is good, wear seems normal and grip doesn't seem worse than PS4s. I would say the noise is slightly louder than Michelin but honestly it's hard to tell without a back to back and because they're 20's, they have a large footprint in any case.

Rim protection is also decent, i've hit a few kerbs side on in multistory car parks and got away without any rim damage, so must work.

I believe the rolling resistance on the Vredesteins isn't as good as the others. I notice a 5mpg change between summer and winter tyres (they're obviously narrower too).

But for the price, no complaints.

FWIW I absolutely loved the Vredestein Ultrac Vorti's I ran on my E39s; superb tyres; very grippy in wet & dry, a great ride (18s) and just as good as PS4s IMO

It was a few other car owners (Porsche and BMW) that my pals look after their cars, who got me onto the Vreds and I'd always recommend them

[Flat6]

March2008 said:

Has anyone put non run flats, such as a Michelin 4s on? And noticed an improvement in ride?

I find the ride pretty good on run flats 75% of the time, but it has this busy feeling through the car that just feels out of place on some roads. Hard to explain, it absorbs pot holes and big bumps fine, but more of a general chatter through the car.

Any thoughts? The car is mechanically perfect I understand. 18 months old.

Just wondering if changing to non run flats will help. Car is on standard M Sport suspension

Thanks

I changed from GY rfts (on 20’s) to PS4S’s and there was a decent improvement in ride quality on my RWD G31 with a lot less of the loud thudding when hitting a pothole (and no sidewall bulges, which the rfts did remarkably easily). Covered 25k and wear on the Michelin’s has been superb with still 4-5mm on the rears. Only negative is a drop in fuel economy, overall average being around 5mpg down but given the rate the Goodyears had to be replaced due to bulges, this isn’t an issue for me.

[March2008]

Stillstand said:

I've done about 10k on the Vredestiens over two summers. I bough them as an alternative to Michelin PS4 that I used to run on my F31, but they were 3-400 a set more in the sizes for the G31 and I didn't want to run non-standard tyre sizes.

They've been solid so far - had no issues. Comfort is good, wear seems normal and grip doesn't seem worse than PS4s. I would say the noise is slightly louder than Michelin but honestly it's hard to tell without a back to back and because they're 20's, they have a large footprint in any case.

Rim protection is also decent, i've hit a few kerbs side on in multistory car parks and got away without any rim damage, so must work.

I believe the rolling resistance on the Vredesteins isn't as good as the others. I notice a 5mpg change between summer and winter tyres (they're obviously narrower too).

But for the price, no complaints.

Thanks for that, I'll give the garage a call later to see what they can do for me.

To be honest, it's one of those things, I'm not sure how much better it will be with the Non-RFs on, and is this actually the issue I'm facing, with the "bobbly" ride, are the tyre walls just too stiff which makes the ride that bit too jiggly. Part of me thinks so, but then part of me thinks it could be down the the M Suspension. I think it was Joe Achilles G31 530d review where the said the tyres, plus being on 20s seemed to unsettle the ride. It's one of those things isn't it? Until you try it and change something you won't know. I'd put 19s on if I could find a reasonable set for the right price, and Non RFs on those.

Wish I could just borrow a set of 19s! And see if it makes the difference. I just love how it looks on 20s... Compromises eh!!

Will keep the thread updated.

[March2008]

Just thought I'd update to say I've put 19 inch 845M style wheels on with Non Run Flat Michelin PS4 tyres. 245/40/19 all round.

After a few good miles testing, it's not a massive difference to be completely honest, not the night and day I was expecting, however, it is better, and crucially, I think it's just the right side of the tolerance threshold now, that was just bothering me. No long do you get the feedback through your bum that just felt wrong, like the wheels were just constantly fidgeting on the surface, bumping up and down. It's taken the edge off it.

The more you think about it when you're driving, the less I noticed it with the 19s, when I have the 20s on, I just found myself noticing it more and more.

I found a nice set from a salvaged 530e with nearly new tyres, they were delivered for £1250. So pretty much the same price as putting a fresh set of tyres on the 20 inch wheels. So hopefully, if all goes well, I can sell the 20s and its cost nothing to test really. Plus.. the 19 inch tyres are a fair bit cheaper for a set.

I'm going to run them for a bit over the winter, then swap the 20s back in the spring, and see if I notice!

Edited by March2008 on Monday 9th December 16:07

[danb79]

March2008 said:

Just thought I'd update to say I've put 19 inch 845M style wheels on with Non Run Flat Michelin PS4 tyres. 245/40/19 all round.

After a few good miles testing, it's not a massive difference to be completely honest, not the night and day I was expecting, however, it is better, and crucially, I think it's just the right side of the tolerance threshold now, that was just bothering me. No long do you get the feedback through your bum that just felt wrong, like the wheels were just constantly fidgeting on the surface, bumping up and down. It's taken the edge off it.

The more you think about it when you're driving, the less I noticed it with the 19s, when I have the 20s on, I just found myself noticing it more and more.

I found a nice set from a salvaged 530e with nearly new tyres, they were delivered for £1250. So pretty much the same price as putting a fresh set of tyres on the 20 inch wheels. So hopefully, if all goes well, I can sell the 20s and its cost nothing to test really. Plus.. the 19 inch tyres are a fair bit cheaper for a set.

I'm going to run them for a bit over the winter, then swap the 20s back in the spring, and see if I notice!

Edited by March2008 on Monday 9th December 16:07

That looks much better IMO

19s are the perfect size; tyres with more sidewall = better drive comfort etc

Sell the 20s; stick with 19s

If you wanted a touch softer tyre; you could look at a set of premium all-seaons like Goodyear or Michelins

I find the Goodyear Vector Gen3s on our F31 (albeit 18s) a very smooth and quiet ride compared to he harder compound of the Assym 6s it runs for summer tyres etc

I've got Michelin CC2s on my 130i and they're much better than the PS5s that was on it when I bought it

[fadfad]

always swapped the runflats off my cars when they wore down to non run flats with a pleasant improvement in ride quality.

however after 4 inconvenient punctures this year I decided to go back to runflats and changed to goodyear all seasons in October.

well, all i can say is runflat tech has improved massively and I cannot notice a ride quality difference which is great news.

[March2008]

Good call, it opens up more options with sensible sized wheels/tyres too. So thanks for that. I'll look at those options when I need to change.

Agreed, I like to see a tyre sidewall too, and the added comfort is a bonus.

danb79 said:

That looks much better IMO

19s are the perfect size; tyres with more sidewall = better drive comfort etc

Sell the 20s; stick with 19s

If you wanted a touch softer tyre; you could look at a set of premium all-seaons like Goodyear or Michelins

I find the Goodyear Vector Gen3s on our F31 (albeit 18s) a very smooth and quiet ride compared to he harder compound of the Assym 6s it runs for summer tyres etc

I've got Michelin CC2s on my 130i and they're much better than the PS5s that was on it when I bought it

[March2008]

fadfad said:

always swapped the runflats off my cars when they wore down to non run flats with a pleasant improvement in ride quality.

however after 4 inconvenient punctures this year I decided to go back to runflats and changed to goodyear all seasons in October.

well, all i can say is runflat tech has improved massively and I cannot notice a ride quality difference which is great news.

That's the dilemma isn't it. I'm not going to tempt fate, I'll look at some inflator options/recovery options! In the past I've had punctures in both run flat and non runflat, the pressure stayed in long enough, but I've also had an occasion where I RFT got me home when I needed to, from the other end of the country at a time when I couldn't stop. So I'm a big fan on that front.

On all occasions, I've never been able to repair a tyre, so that's not even a consideration. It's just getting you home. These days if I have a puncture, I just assume its a new tyre! It lowers your expectations. I was pretty gutted when it was a near new Michelin PS4 on a 275 width....

I think as long as I have a G31 with Sport Suspension, it'll have non RFT.

[eddy77]

I dropped from 20” and RFTs on my G30 (no adaptive) to OEM 19s and non RFT and it transformed the car. Subtle at first but over the next six months it was night and day on a variety of roads. Best thing I ever did. I put Goodyear Assy 6 on so softish tyre too. Loved that car once it was done (now sold).

[BMWSIMAN]

I also dropped from 20" RFs to 19" non-RFs (on BBS wheels) and it has transformed the ride, which I can only describe as being "brittle" before. The 20" tyres the car came on were Pirelli PZ4s and I've stuck with those, (just in the 19", Non-RF size). Widths are the same but new bolts were needed. The TPS were easily swapped. Go for it.