Last post on Sep 19, 2012 at 10:26 AM
You are in the BMW Z4
What is this discussion about?
BMW Z4, Coupe, Convertible
#29 of 82 Tire information
Nov 12, 2007 (12:13 pm)
From earlier posts, it seems like there is confusion on the stock tires for a Z4. I bought a new Z4 Coupe in August, 2006 and it came with Potenza RE050A's. I did not get the sport package because I intended to drive the car year round (I live in the suburbs of Chicago). To quote a review of these tires, "do not even think of driving on this tire in the snow, or even when the temperature gets down to freezing". I didn't kill myself, anyone else or even put a dent in the car, but I credit that to many years of experience driving in snow and ice, plus autocrossing and SCCA experience.
BMW does not offer an all season tire for the Z4, and neither they nor the dealer will tell you that the RE050A is a summer performance tire. I emphatically told the dealer that I was going to drive the car year round, and all I got was a mild suggestion that I might want to "think about" getting an extra set of tires.
#30 of 82 Re: Tire information [major914]
Nov 13, 2007 (7:29 am)
I got a set of wheels/snow tires from Tirerack for my 3.0Si WITH tire pressure sensors for aabout $1200. That's a small price to pay for winter security. Also, if I choose to sell the car, the winter set will always be sellable.
#31 of 82 Re: Tire information [esfoad]
Dec 02, 2007 (12:48 pm)
I am picking up a used Z4 next week. What wheel/tire set did Tirerack recommend (sizes, brand, etc.)? BTW, I've used Tirerack for years, and swear by them!
#32 of 82 Problems with Potenza RFTs (Run Flat Tires)
Jan 30, 2008 (5:17 am)
Has anyone encountered any wear-related problems with the Bridgestone Potenza RFTs (Run Flat Tires)? I've got a 2005 Z4 3.0 with the sport package (18" wheels) and after 22k miles my tires are bad. The inside edge is completely worn down while the outside edge looks fine. I'm guessing that this is a problem with alignment (camber toed inside) but the problem is consistent with all four tires. I bought the car new from the dealership and it seems like this was "perfectly misaligned" since the beginning.
Of course, the dealership (Classic BMW in Dallas) will have nothing to do with me over the matter and a new set of exact replacements is $1700 from Firestone (including install & tax). I'm hestitant to get non-RTFs because of the problems I've heard and because there is no place to put a spare.
First, has anyone else experienced this type of problems with their tires and/or alignment? Second, make sure you know what you're getting yourself in to before you purchase this car -- it's a great ride by VERY expensive to fix ANYTHING (including tires).
#33 of 82 Re: Problems with Potenza RFTs (Run Flat Tires) [djbarker1]
Feb 04, 2008 (4:14 pm)
All BMW's have the tire wear that you describe to some degree, regardless of tire brand. I have read many letters to the editor in the BMWCCA magazine "Roundel" about this issue. It has to do with how the suspension is configured, so you can drive the car more aggressively on the road. I believe its called "negative camber setup", but I could be mistaken...It gives the car a "squatty" look when cornering. Compounding this issue is that performance tires are made of a softer compound, which gives better traction, but poor tread-life.
See if you can obtain a few issues of ROUNDEL and you will see that others have the same "Issue" (I hesitate to call it a complaint, only because many buyers prefer the BMW setup so they can enjoy the "Ultimate Driving Experience"). Of course, this little "item"is seldom brought up by the car salesman...
#34 of 82 Re: Problems with Potenza RFTs (Run Flat Tires) [djbarker1]
Feb 04, 2008 (4:53 pm)
I have the same car 2005 Z4 3.0 with the sport package (18" wheels). I bought the car as a certified used BMW 4months ago. It has 26K miles on it. At the time of purchase the dealership had replaced the back tires, but the founts were good as the previous owner had recently replaced. Shortly after I got the car I noticed it was very squirrelly on uneven road surfaces to the point I thought it was dangerous to drive. I documented the issue and took it in for service. At that point they did an alignment, but told me they were not satisfied with the results. They got approval from BMW to do what was called a steering column replacement. It took about a2 days to complete. 90% of the problem went away, but occasionally depending on road surface the car would want to pull to one side or the other. I'm talking a quick darting type pull. This weekend I noticed the inside treads of only one of the front tires worn smooth about 1 1/2 inches across the tire. Tomorrow I am planning on replacing the Potenza RE050A's with Mich Pilots $236 each, and buying an auto air compressor with tire sealant. This should guard against anything but a total blow out. It seems several people on this post have done the same thing with very good results. BMW sells the inflation kit or you can buy a good one at an auto parts store for 50% the BMW price
#35 of 82 Re: Problems with Potenza RFTs (Run Flat Tires) [drtk]
Feb 04, 2008 (5:18 pm)
That twitchy, tugging steering on grooved pavement is called tramlining. It's not unusual with high performance tires.
#36 of 82 Re: Problems with Potenza RFTs (Run Flat Tires) [fedlawman]
Feb 04, 2008 (7:29 pm)
Some will say tramlining is more pronounced with run flats. I also was told the stiffer sidewall of a runflat can affect the tracking characteristic in cold weather. Do you know if tramlining is generally better or worst with a run flat?
#37 of 82 Re: Tire information [hydro333]
Feb 05, 2008 (3:42 pm)
OUCH! Sorry for the delay but this is what I bought from Tirerack based on their recommendation.
4 - 205/50VR-17 Dunlop SP Winter Sport 3D Tires
4 - 17x7.5 Sport Edition A7 Silver Wheels
4 - BMWSEN1 Tire Pressure Sensors
They are perfect.
#38 of 82 Re: Problems with Potenza RFTs (Run Flat Tires) [drtk]
Feb 17, 2008 (8:35 am)
I have the sport package also. The Potenza's are only good for about 20K then they are trash. That is the catch to run flat sport tires. The run flats I had on my Corvette lasted about that long also. These tires are also horrible in any type of foul weather.Try replacing them with the pirelli all season runflats. Or you can replace them with non-runflats and keep a lot of goo and a small compressor in the trunk.