[IAmATeaf]

Finally managed to get rid of my run flats all round. Have Continental SP5 non RF on the back and had Goodyear Asym2 RF on the front.

I always found my car very fidgety to drive especially when pushing it at higher speeds, much preferred my old Honda Accord when driving on the motorways/freeways.

I toyed with the idea of going for a different profile up front but then decided to simply stick with the current staggered setup and went for Michelin PS4S non RF XL tyres and boy what a difference they have made. The fidgety-ness has gone and so has the front end crashing when going over rough surfaces. The car is now so much nicer to drive, the only negative is that the new tyres are noisier and am hoping that they'll quieten down over time.

I used to run my car at around 38psi all round but currently have it set to around 35 all round, might experiment over the next few weeks to see which I prefer and a last comment for anybody unsure, just do it and get rid of the RF the first opportunity you get

[J.D.]

Totally agree. The difference in the ride and handling is well worth it.

[ufogto]

Originally Posted by IAmATeaf

Finally managed to get rid of my run flats all round. Have Continental SP5 non RF on the back and had Goodyear Asym2 RF on the front.

I always found my car very fidgety to drive especially when pushing it at higher speeds, much preferred my old Honda Accord when driving on the motorways/freeways.

I toyed with the idea of going for a different profile up front but then decided to simply stick with the current staggered setup and went for Michelin PS4S non RF XL tyres and boy what a difference they have made. The fidgety-ness has gone and so has the front end crashing when going over rough surfaces. The car is now so much nicer to drive, the only negative is that the new tyres are noisier and am hoping that they'll quieten down over time.

I used to run my car at around 38psi all round but currently have it set to around 35 all round, might experiment over the next few weeks to see which I prefer and a last comment for anybody unsure, just do it and get rid of the RF the first opportunity you get

It sounds like the reason your car was fidgety is because you had mismatched tires and your tire pressure was too high. Probably the high tire pressure to blame more than the mismatched tires.

38 Psi cold would turn into 41-42 psi on the highway. That is usually way too high. When you over-inflate a tire, part of the tire is no longer in contact with the road. When less of the tire is in contact with the road the car handles worse.

[IAmATeaf]

What mismatched tyres? I had a pair of asym2 on the front and continental SC5s on the back, I still have the contis on the back but now have a pair of PS4s on the front. The door card indicates that for normal driving the tyres should be set to 37-38 all round.

[mrphotoman]

lol you have 2 different brand tires on your car with different tread patterns. it is common sense that is the wrong thing to do. did the tire store not tell you it was a bad idea? if not i would shop somewhere else next time. you may want to get those mismatched tires replaced asap.

[bmwchue]

Originally Posted by mrphotoman

lol you have 2 different brand tires on your car with different tread patterns. it is common sense that is the wrong thing to do. did the tire store not tell you it was a bad idea? if not i would shop somewhere else next time. you may want to get those mismatched tires replaced asap.

theres nothing wrong with having 2 different brand tires as long as both are on the front or back. but for an xdrive you will want all 4 same tires

[cfm56d7b]

Originally Posted by bmwchue

theres nothing wrong with having 2 different brand tires as long as both are on the front or back. but for an xdrive you will want all 4 same tires

Well - this is not necessarily accurate. Mixing summer performance and all season tires on front and rear axles is the least desirable situation. These tires are made different compounds (all season tires are softer to accommodate colder temperatures) and handling characteristics in emergency situations will cross into a risky territory.

[IAmATeaf]

My car is RWD so having differing make performance tyres on the front and rear axles isn’t an issue as I ensure that the same make/model are on the same axle.

[Spaceme1117]

Getting rid of the stock 225-45r18 Pirelli run-flats today. Am replacing them with Michelin Pilot Sport A/S 3+ in 245-40r18 size. Should be a big improvement in grip, ride comfort, and handling.

[Bmwman325]

Originally Posted by Spaceme1117

Getting rid of the stock 225-45r18 Pirelli run-flats today. Am replacing them with Michelin Pilot Sport A/S 3+ in 245-40r18 size. Should be a big improvement in grip, ride comfort, and handling.

I just did this. Tires are amazing, car rides completely different in a good way. And I can finally drive in some snow without fear of crashing...

[Spaceme1117]

Update. Got the Michelin A/S 3+'s installed. Can tell a huge improvement right away. Ride is much more comfortable and much less bumps transferred to the rest of the car.

[luckstr]

Originally Posted by IAmATeaf

Finally managed to get rid of my run flats all round. Have Continental SP5 non RF on the back and had Goodyear Asym2 RF on the front.

I always found my car very fidgety to drive especially when pushing it at higher speeds, much preferred my old Honda Accord when driving on the motorways/freeways.

I toyed with the idea of going for a different profile up front but then decided to simply stick with the current staggered setup and went for Michelin PS4S non RF XL tyres and boy what a difference they have made. The fidgety-ness has gone and so has the front end crashing when going over rough surfaces. The car is now so much nicer to drive, the only negative is that the new tyres are noisier and am hoping that they'll quieten down over time.

I used to run my car at around 38psi all round but currently have it set to around 35 all round, might experiment over the next few weeks to see which I prefer and a last comment for anybody unsure, just do it and get rid of the RF the first opportunity you get

Just to confirm, you were driving your Run Flat's at 38 psi and when you changed to non Run-flats you are driving around at 35psi, correct? Thanks

[IAmATeaf]

Yes but only as the tyre place set them all to around 35-36, I’ve since pumped them up to 37 and plan to set them to that from now on.

[luckstr]

Originally Posted by IAmATeaf

Yes but only as the tyre place set them all to around 35-36, I’ve since pumped them up to 37 and plan to set them to that from now on.

Thanks for clarification. I am just about ready to dump the RFT's and get non RFT's (not sure which make yet); door placard (2017 440i convertible) says 36 front and 41 rear but that's for RFT's, so I'll probably try 34/38 on non RFT's).

[IAmATeaf]

Mine are 19s and my door card states 37 all round. I will experiment over the next few weeks to be honest to see what I prefer.

[luckstr]

Originally Posted by IAmATeaf

Mine are 19s and my door card states 37 all round. I will experiment over the next few weeks to be honest to see what I prefer.

As are mine, let me know your findings, please. Thanks

[Spaceme1117]

Originally Posted by luckstr

Thanks for clarification. I am just about ready to dump the RFT's and get non RFT's (not sure which make yet); door placard (2017 440i convertible) says 36 front and 41 rear but that's for RFT's, so I'll probably try 34/38 on non RFT's).

Tire pressure is independent of what kind of tire you have on your car whether it be runflats or not. That being said, I would not go any lower than 1 or 2 PSI lower than what it said on the door placard.

[IAmATeaf]

My PS4S tyres have now quietened down, still very happy with the tyres and car, will be replacing the Continent SP5 tyres on the back with these when they need replacing.