[PoutineMachine]

I was right about to walk into the paperwork office when I noticed the 225 on the rear. I measured the front and rear and sure enough both were the same size. After some arguing I got the dealer to replace the rear rims and the tires but from what I'm being told the car is also limited to 130mph.

[Pray for Mojo]

It took a while of back and forth but my dealer is going to replace my rear rims at no charge to me. BMW Canada didn't want to do anything but Calgary BMW stepped up. Just waiting for them to arrive and then it's PSS time. I'm hoping the speed limiter can be adjusted with coding.

[FoxCrane]

Just out of curiosity, since I don't really know enough about tires, is there an advantage to having the rear tires wider than the front? I'm getting a 228xi MSport with mixed summer tires. Is there a performance difference between the mixed summer tires vs someone who initially opts for all-seasons and installs summers on the same size wheels front/back?

[ntrinsik]

Not sure on the BMW, but my previous car (G35 Coupe) had staggered tires. Moving to a square setup, in this case 255/35/18 all around, reduced understeer.

[FoxCrane]

Is the consensus that a square setup with same width tires is better than the staggered setup where the rear tires are slightly wider?

[mjposner]

Pros: 4 wheel tire rotation (unless you get unidirectional tires), cheaper to buy tires, less understeer

Cons: Fat rear tires look damn cool!

[bernstem]

Originally Posted by FoxCrane

Is the consensus that a square setup with same width tires is better than the staggered setup where the rear tires are slightly wider?

There is no way to say one setup is better than another as it depends on the rest of the suspension, car setup and driver preference. In general, increasing front tire width or decreasing rear width will reduce understeer (or increase oversteer). Decreasing front tire width or increasing rear tire width will increase understeer (or decrease oversteer).

As an example, if a car has a staggered setup, is currently understeering and you want it to behave neutrally or with oversteer, then going to a square setup would help. Most cars are designed with understeer from the factory as it is more predictable for the average driver. For those cars, moving to a square setup is "better" to many people. I have not had the opportunity to drive the 235 hard enough to get a feel for its suspension nor have I seen it explicitly stated in a review, but I highly suspect the stock setup understeers.

[jet987]

Can someone post pics of a rear 3/4 view of an m-sport with a square all season setup? I've seen several pics of the summer staggered setup but not the all seasons. I'm debating on ordering the all seasons or summer setup for snow driving here in Chicago but like the look of staggered wheels.

[Béhème]

Originally Posted by GFK007

Guys,

The AS are 225 on all four tires. I understand the summers are staggered.

Can I throw a set of staggered performance tires on the existing set of stock rims?

Originally Posted by prozzi20

When I looked at rear tires 245/35/18 it says minim rim size is 8". Will they still fit 7.5"?

Mounting a wider tire on a relatively narrow rim will actually decrease the contact patch, so even though it may fit, it would be defeating the purpose. This happens because it pinches the tire at the rim and causes the thread of the tire to become convex.

In fact, for racing purposes, a tire performs better when mounted on the widest rim width in it's recommended range.