New Tires!!

[35iDriver]

Just put a new set of Michelin "Pilot Super Sport" tires on my 35i. This model tire basically replaces the PS2's.

Car now drives and handles much better than it did with the OEM Bridgestone runflats.

Went with 225-40-18s in front to match the OEM size, but bumped the rear width from 255 to 265. 265-35-18.

4 tires, purchased at local Discount Tire store. Inc: Install, Lifetime spin balance, 4 Rebuilt TPM systems, stems, Environmental Fee, Tire disposal, Lifetime rotation..................$1007 + tax.

[jparnes1]

You got a good deal, but you'll never take them up on the free tire rotation.

[GaryRudolph]

Originally Posted by 35iDriver

Car now drives and handles much better than it did with the OEM Bridgestone runflats.

How is the tire noise now?

[2045]

Originally Posted by GaryRudolph

How is the tire noise now?

2nd that. and also, how much of a improvement on the ride compare to the Runflats? i'm running 19'' but also thinking about switching to the PSS.

[35iDriver]

Originally Posted by jparnes1

You got a good deal, but you'll never take them up on the free tire rotation.

They are different sizes front to back but the Pilot Super Sports can be rotated side to side, because they are not unidirectional. The only time I'd rotate would be if there was uneven wear when comparing left to right or if one side started cupping.

[35iDriver]

Originally Posted by GaryRudolph

How is the tire noise now?

Tire noise is much less now, but don't forget we are comparing new tires to runflats with 25k on them. I do not recall the noise level when the original runflats were new.

[35iDriver]

Originally Posted by 2045

2nd that. and also, how much of a improvement on the ride compare to the Runflats? i'm running 19'' but also thinking about switching to the PSS.

The runflats were at 4/32 tread depth, so we are not comparing to bald tires, but they were definitely past their "performance" prime.

Comfort - Comparing what you feel in the drivers seat when going over bumps or holes in the road is like night and day when comparing the old to the new tires. Much smoother now over imperfections in the road.

Handling - I had no confidence in the runflats the past 5k miles or so as the car would slip if I pushed past 6/10ths going into a 90 degree turn and it always felt like it might slip at any time going over 6/10ths on an onramp with a considerable arc. I do not believe I ever had confidence pushing past 8/10ths when the runflats were new. I can push the car 9/10ths now in the same situations with confidence. It seems much more planted to the road.

[flpnout]

That does it, I'm dumping the runs flats come summer! What's the benefit of going 255 to 265? Not sure what that does?

[Vintage]

We dumped the runflats 15k miles ago and no looking back - RFTs on a sports car are idiotic.

[35iDriver]

Originally Posted by flpnout

That does it, I'm dumping the runs flats come summer! What's the benefit of going 255 to 265? Not sure what that does?

I kept 225s on the front. Went from 255 to 265 on the rear. That increases the contact patch. Additional traction.

[flpnout]

Originally Posted by 35iDriver

I kept 225s on the front. Went from 255 to 265 on the rear. That increases the contact patch. Additional traction.

It makes it a bit more wider. I'll see if I can do that with 19" wheels. Thanks!

[jannisa]

Originally Posted by 35iDriver

I kept 225s on the front. Went from 255 to 265 on the rear. That increases the contact patch. Additional traction.

... additional understeer would be more accurate

[fre2bpowerless]

I'll be looking for a new set soon, does it make sense going any wider in the front?

[35iDriver]

Originally Posted by jannisa

... additional understeer would be more accurate

More accurate when discussing the effects wider tires have when the vehicle is going in any direction other than a straight line.

Traction is the more general term and applies to when the vehicle is going in any direction (straigt line or turning)

[cdeslandes]

Originally Posted by 35iDriver

The runflats were at 4/32 tread depth, so we are not comparing to bald tires, but they were definitely past their "performance" prime.

Comfort - Comparing what you feel in the drivers seat when going over bumps or holes in the road is like night and day when comparing the old to the new tires. Much smoother now over imperfections in the road.

Handling - I had no confidence in the runflats the past 5k miles or so as the car would slip if I pushed past 6/10ths going into a 90 degree turn and it always felt like it might slip at any time going over 6/10ths on an onramp with a considerable arc. I do not believe I ever had confidence pushing past 8/10ths when the runflats were new. I can push the car 9/10ths now in the same situations with confidence. It seems much more planted to the road.

I've gained 10% cornering speed with the PSP over the OEM tires. And they're more comfortable!

[35iDriver]

Originally Posted by cdeslandes

I've gained 10% cornering speed with the PSP over the OEM tires. And they're more comfortable!

You mean Pilot Super Sports (PSS)?

[az34]

great move but what will you do if you get a flat tire in the middle of nowhere. my fear.

[35iDriver]

Originally Posted by az34

great move but what will you do if you get a flat tire in the middle of nowhere. my fear.

Life is full of trade-offs. It's all about Risk vs Return. The risk that I will get a flat in the middle of nowhere is so low that it is not even close to the benefit I get from having the additional performance from non runflat tires.

100s of thousands of sports car owners have all made the same decision as me, otherwise there would be no demand and tire manufacturers would have already stopped making Z rated non runflat passenger car tires by now.

BMW Assist eliminates almost all risk of being stranded.

In addition, I've driven in the middle of or at the edge of "somewhere" for about 99% of the miles I put on the car since I've owned it.
I recall being in the middle of nowhere for a few miles a few months ago, but before I knew it I was right back within a stones throw of somewhere

[robertrichhart]

Originally Posted by az34

great move but what will you do if you get a flat tire in the middle of nowhere. my fear.

Just get a small air pump and a bottle of tire "Slime" , and that's only for if BMW assist doesn't show.. 98% of all flats on the road are due to a small puncture. I carry a tire plug kit as I'm comfortable making that kind of repair on the road. Not much risk from my prospective... I'm changing from the OEM runflats just as I did on my '03, with no regrets...

[Colorado]

As I wrote in another thread---BMW Roadside Assistance is only good for $100.00 per incident. With a hook up charge of $65.00 to $75.00 plus $4.00 to $6.00 per mile, you don't go far. Out in the middle of nowhere is closer than you think. I will consider changing out the OEM tires when my car gets here. Maybe I can find someone who takes new car "take off's" as trade in. I have a BMW mobility kit left over from my Mini Cooper S. They gave it to me when I bought the Mini. I would hate to try and use it on a dark night ou in the midle of nowhere. The tire plug kit is a better way to go and no slime in the tire. Better yet, State Farm Insurance for $3.00 every 6 months and they will tow you wherever you need to be towed for the repair. AAA Colorado is $112.00 for basic plan and you will be towed up to 4 miles. The Plus Plan for $200.00 per year gets you towed up to 100 miles. Damaged wheels, flat tires (run flat or non) you decide which coverage is best for you and where you drive. I have AAA, State Farm Insurance, and BMW roadside assistance when my Z4 gets here. I know who I am going to call if I have cell service from the middle of nowhere.

[Vintage]

TRADEOFFs:

RFT = crappy performance all of the time, loud road noise all of the time, uncomfortable over bumps, expensive to replace ($400 a piece or more)

NRFTs/Real Tires = quieter, more comfortable, much better performance, and on rare occassion - stranded for a while with $100 out of pocket (maybe)

We all make our choices but I will take the Real Tires and did so a while back - awesome and I can't wait for the next set as they will be the new Michelins.

[HenryHank]

I'm dumping the RFTs soon. I just bought my 2010 Z4 35i a couple of weeks ago, and I was coming off of the Merritt Pky in CT onto a hairpin turn off the highway (King Street South exit)-- a turn my M5 could make no problems at the speed I was going (maybe 30-35mph) and the RFTs broke loose and I lost control and slide into the opposite on-ramp to the hightway. LUCKILY there wasn't another car there, so I could turn back into my lane and on my way, but WOW, I never expected the tires to give way that easily. Granted, it was also colder out (in the 40s), and I was going faster than I should have been, so it's not all the tire's fault. But I can't wait to dump these RFTs.

Here's the exit (I was driving west/"down" in the pic): http://maps.google.com/maps?q=merrit...rce=gplus-ogsb

Actually, here's a better view from driver's perspective: http://maps.google.com/maps?q=merrit...rce=gplus-ogsb

I'm a big fan of the BFGoodrich g-Force Sport which is what I have on the M5 and my previous 325i. I haven't decided to go with the g-Force Sport for the Z4 or go all-season with the Continental ExtremeContact DWS so I don't have to swap wheels each winter.