Last post on Sep 19, 2012 at 10:26 AM
You are in the BMW Z4
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BMW Z4, Coupe, Convertible
#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.
#39 of 82 Driven
Feb 17, 2008 (8:44 am)
The Z is for driving and hence you can drive the tires right off...in about 20K. My experience with these runflats (Potenza) and other runflats (on Corvettes) is that they are sport/performance tires which means they have a very soft compund that lasts 20-25K then they are shot. So if you are buying a performance car you have to be prepared to deal with the fact that you will be replacing tires on a regular basis. That being said, most of the runflats I have had wear quickly but most hold their composure. The potenzas seem to twist and cup excessively with time. My personal opinion is that they are trash. I would try either another brand of runflat or a regular tire and keep a small compressor and goo in the trunk if it is time for tire replacment.
#40 of 82 Z4 M stock tires
Feb 19, 2008 (7:43 pm)
Can somebody tell me what are the stock tires on Z4 M Roadster? Are they summer or all-season?
#41 of 82 Re: BMW Z4: Tires/Wheels
Feb 27, 2008 (11:21 am)
I was the fortunate second owner of the most pristinely new, babied 2004 BMW Z4 2.5i convertible. After 2.5 years with the first owner, it was only driven 11,400 miles. It was kept in a garage at home and at work. Distance to work? 5 miles. The car seldom saw speeds above 40 miles an hour. It got garaged for the winter months. It seldom saw a drop of rain.
Ah, the tires. Standard Potenza's High Performance ZR Run Flat Tires (RFT) with little to no wear. I have been driving the car between north of Baltimore to south of Washington DC at a 2000 mile a month pace. I picked up the car Oct 06 and dry docked it for Dec, Jan, Feb. Tire wear for highway miles was negligible. It rain straight and true as the most perfect balance of roadster and performance tire I have ever experienced. That was my first 10,000 miles.
Around 22,000 miles, i picked up a small steel filament puncture in both driver side tires (months apart - Spring of 2007 and late Summer 2007) and both near the inner side wall on the bottom tread. Finding a place to plug a RFT is next to impossible. They want to sell you that $200 and up replacement tire in the worst way. "We were going to fix it for you, but ooops, its near the part of the tread near the side wall. Sorry - we won't touch it." So I squirted a couple of cans of fix flat goo into each tire and got easily another 10,000 miles out of these tires. I heard so many neigh sayers, "It will make the tires run unbalanced" or "It will ruin the tire." Poppiecock and bulltwinkies - if I couldn't use the fix flat goo, the tires were shot anyway. They are riding fine and holding tire pressure no problem. What's more, they are wearing evenly!
Where I think I goofed was I didn't dry dock the car again for the winter months (2007 to 2008). I drove it all of December 08 and January 08 as they were abnormally Northeast mild but a specially snow and ice free. What I experienced could only be compared to the exorcist on mornings below freezing. The summer RFT's take a set while the car is parked over night. The first 10-15 minutes are a challenge of every fiber in ones' body. At speeds under 25-30 mph, there is a subtle wub-wub. At speeds of 40 mph and up, the steering wheel begins shaking violently and doesn't stop until the tires have warmed.
As it turns out, I had to bring the car in for only its second service, an oil change early Feb 2008. Low and behold, with nearly 32,000 miles on the tires, they are beginning to get close to the wear indicator marks for the rear tires. A few wet cool morns, accellerating into traffic, the back was breaking free a bit with ever increasing frequency. I think if I baby the car, don't jump on it ever and only drive it when temps are over 40 degrees F, I may get another 5,000 miles out of them. The most beautiful thing is the wear has been totally even with no inside or outside wear deltas. If someone has wear only on the insides, it sounds like a definite toe, balance. alignment, or driving consistently at excess speeds on consistenly windy roads issue. I've dry docked the car now and won't drive it until late March.
Because of the "unrepairable" punctures, instead of just replacing the rear tires, I'm thinking of getting an entire new set of 4. Problem is, even with internet tire purchase, the Factory OEM as everyone knows are freaking expensive. I'm willing to try Non-RFT, but haven't heard anything good about them on the Z4. I've hear that GoodYear are a solid replacement, but don't wear as well.
I would even consider going with something less than ZR rated because I seldom even drive over 80 mph. I like the idea of All Season High Performance because odds are I will not have the luxury of dry docking her in future winters (my son gets his license and will take my non-Z4 set of keys).
Does anyone have any recommendations on off brand RFT or non-RFT replacements they have had good luck with?