[TLL0003]

I am in need of new tires on my 2014 328i M sport. I have a staggered setup with sizes 225/45/18 in front and 255/40/18 in rear. Currently I am running continental contisportcontact 5 SSR run flats and I'm not a big fan. The only options I've found for the front are these same tires, Bridgestone potenza s001, and Pirelli centuratos. It looks like a lot of people are ditching the run flats for some better performing non run flats, but this is a daily driver and I do not want to get stranded. My question is, what are my options for tires in this size and will a better differently sized tire fit m current wheel? For those that ditched run flats, what do you have and what do you do if you have a flat?

It doesn't look like there many good run flat options in the front size, so what is ,y best option for tires?

Also, I would like summer performance tires over all season.

Thanks in advance

[alohasurftoad]

my m-sport came with staggered bridgestone s001 runflats and to me the ride, noise and handling are fine. many others have complained that they are too rough riding and loud, idk.

currently, i have aftermarket wheels with go-flats and carry a scissors jack, 17mm lug wrench, compact tire inflator and tire plug kit if i take a nail. if you have a severe pothole type blowout a runflat will not help you there anyhow. some peeps also carry compact spares if/when they feel the need.

i do recommend you go to a wider front tire instead of the 225. the front wheel is 8" wide and can accept 235/45R18 or 245/40R18 (what i'd do) and it will mitigate the some of the understeer associated with the stock staggered setup.

[.BMW.]

If you want more alternatives look for 245/40-18 front and 255/40-18 rear or 245/45-18 front and 255/45-18 rear.

To achieve the best stance the above tire sizes can be combined with 10-15 mm rear spacers.

[Professor///M]

Originally Posted by .BMW.

If you want more alternatives look for 245/40-18 front and 255/40-18 rear or 245/45-18 front and 255/45-18 rear.

To achieve the best stance the above tire sizes can be combined with 10-15 mm rear spacers.

I don't understand how these other tire sizes are helpful. I'm in the same situation as the OP but want to ditch the bridgestones. Thinking Mich PSS.

Please educate me

[alohasurftoad]

the 245/45R18 and 255/45R18 size .BMW. suggested is actually too tall and will affect with varying degrees, the speedometer, odometer and performance since the gearing at the wheels is taller and the sidewall is taller.

i've suggested wider tires (245 instead of 225) on the 8" front wheels to reduce the understeer associated with the factory stagger. if you're not concerned with understeer, the factory sizing and stagger is fine.

on x-drives, the difference in diameters between the fronts and rears should not be greater than 1% or it will affect the computer controlling the xdrive. since the op listed non xdrive the 1% is not mandatory however it's still probably a good thing to follow.

the overall tire diameter on the Fxx series should be plus of minus a few tenths of 26" to maintain your speedo/odometer accuracy and factory gear ratio at the wheels.

hope this helps

[Professor///M]

Originally Posted by alohasurftoad

the 245/45R18 and 255/45R18 size .BMW. suggested is actually too tall and will affect with varying degrees, the speedometer, odometer and performance since the gearing at the wheels is taller and the sidewall is taller.

hope this helps

This is what I thought. thanks

[.BMW.]

It all depends what the purpose with the car is.

For a track car maybe not.

But for a daily driver slightly taller tires have a lot of pros:
- Fill the wheel wells better
- More accurate speedometer (all BMW tend to show higher speed than actual)
- Improved fuel consumption
- Better wheel protection

On my F11 I have 5% taller summer tires and 4% taller winter tires compared to OEM size. The speedometer is perfectly correct with the winter tires on and show less than 1% lower speed than real with the summers.

255/45-18 is 3.9% taller than OEM 255/40-18 (245/45-18 is 2.4% taller), so it will result in a perfectly accurate speedo!

[alohasurftoad]

[QUOTE=.BMW.;19982157]It all depends what the purpose with the car is.

For a track car maybe not.

But for a daily driver slightly taller tires have a lot of pros:
- Fill the wheel wells better
- More accurate speedometer (all BMW tend to show higher speed than actual)
- Improved fuel consumption
- Better wheel protection

yes, all this is true. you'll even accrue less mileage on the odometer :-)

maybe something to consider...