February 28, 1999
By: Robert Leidy

After only 16,500 miles on the stock Dunlop SP8080 tires, it was already time to replace them. It was fun for awhile driving around Dallas with bald/slick tires. Very little effort was required to start the back end sliding out around turns (sometimes even when I wasn't trying). But soon the fun wore off, and the realization that the M roadster wasn't carrying a spare tire led to me finally accept that it was time to start the very "unfun" task of shopping for and purchasing new tires.

As I started my tire shopping research I found that the more I learned about tires the harder the purchasing decision became. To many options, to many variables and quite honestly to many opinions. To make the selection process easier I decided to start with the sizing advice posted on the Z3 tire FAQ. I then turned to the highly praised www.tirerack.com website, and decided to consider it the gospel source of tire information. There is always going to be differing opinions so I decided to put on blinders and just focus on what they recommended. Shopping for tires is both confusing and frustrating, I figured making this 1st decision would make the process easier.

2nd decision: I convinced myself that putting anything less than "maximum performance" tires on the M roadster defeats the purpose of purchasing an M roadster. So I click on the Tire Rack's list of "maximum performance" tires and consider their recommendations as the initial candidate list. This narrowed to the field down to 7 tires

• BFGoodrich g-Force T/A KD
• Bridgestone Potenza S-02
• Bridgestone Potenza S-02 Pole Position
• Dunlop SP Sport 9000
• Michelin MXX3 SX
• Pirelli PZero System
• Yokohama Nexus

The first tire to be eliminated from the list was the Dunlop SP Sport 9000, for no better reason other than spite. I hate the Dunlop-sided SP8080E chunks of lopsided rubber provided with the stock M roadster. Besides being out of round I'm purchasing new tires after only 16,500 miles. I realize the stock setup used SP8080E and not these SP9000 tires but I will not even look at the Dunlop brand name (like I said, for no better reason other than spite).

For the remaining 6 tires I made the assumption that were all worthy candidates, but before I was ready to start comparing their individual merits I had one other requirement. I had made the decision to step up the tire size on both the front and back to protect the expensive rims on the M roadster. So the stock 225/45/17 on the front will become 235/45/17 and the stock 245/40/17 on the back will become 255/40/17.

Using some formulas posted on the www.tirerack.com web site I determine that going up one size will have the following affect: Fronts get .35" taller and .39" wider, rears get .31" taller and .39" wider. I realize that different manufactures have slightly different sizes but I'm going to ignore that fact and blindly continue on (remember this is already confusing and frustrating, why complicate things).

The wider tires will help protect the M rims (that are currently wider than the stock tires) and the taller tires will help make up some of the speedometer error (which is a poor excuse because I really don't care about that). Now that I knew what tire sizes I wanted, two additional tire candidates were eliminated because they were not made in the sizes I wanted.

I was down to four candidates that matched my performance and size needs. It was finally time for the final showdown. I decide the wear rating (even though I realize makers rate their own tire) and price will determine the winner.

• Bridgestone Potenza S-02 Pole Position - $964 [180AA]
• Michelin MXX3 SX - $1010 [140AA]
• Pirelli PZero System - $984 [140AA]
• Yokohama Nexus - $490 [160AA]

What stood out from that list was that the Yokohama Nexus tires were about half the price of the other three candidates. My first reaction was "what's wrong with them", so I posted questions to the BMW roadster message board and call the Tire Rack directly. No one had anything bad to say about the Nexus tires and the Tire Rack said they are 99% as good as the Pole Position tires but at half the cost.

So that was it, the decision was made and the tires were ordered. Just under a week later the new tires were delivered and installed locally by National Tire and Battery. NTB charged $9.99 a tire for mounting and lifetime balancing making the total price of the four tires (with delivery, mounting, balancing and tax) $577.

100 Miles Later:

The traction appears to be superior to the stock Dunlop SP8080E tires. At this point the tires feel "stiffer". Maybe that is what the experts call sidewall flex, I don't know the technical term they just feel stiffer. The downside to this stiffer feeling is they are a little harsher in regard to ride comfort (CD Player is skipping a little more than it use too). The Nexus tires also appear to be noisier, I haven't noticed it at highway speed but around town they seem a little noisier.

The pictures above and below show the front and back tires. In both cases I think the larger (than stock) width tires look better and more proper. The rubber is just slightly wider than the wheel surface and sidewalls appear to be straight up and down (instead of angled in like the stock tires). The tread pattern also looks sporty and just different enough to catch your eye.

So at this point I am very happy with my purchase, I feel like I got top notch tires at half the price. But this is just how I feel after 100 miles, I will add another update once I get a couple thousand miles on them.

16,500 Miles Later:

I'm mildly impressed with the wear I'm seeing after 16,500 miles. I have as many miles on these tires as the initial Dunlop 8080E tires. The Dunlops were nearly bald after 16,500 miles and the rear Nexus tires appear to have at least another 2,000 miles in them (the fronts a lot more).

On the negative side I've been caught by surprise a few times in the rain when the traction broke loose sooner than I expected it too. On one very scary occasion, there didn't appear to be any standing water on the hiway but at 70mph I felt the car drift and noticed I was no longer in control. Ended up spinning and sliding onto the soft but flat shoulder. Luckly no damage, and no one else was around me when it happened but it could have been a bad accident.

I did pick up a nail during around 10,000 miles, a Z rated patch plug repaired the damage. While repairing the damage I had time to inspect the wheel wells and I did notice a tiny spot were the front tire had rubbed against the wheel well on each side. The spot was small and had not rubbed through the liner. I guess this tells me that the wheel did make contact with the liner but only a few times so it must have only happened a few times. When it comes time to replace these tires I'm not sure if I will stick with the 235 or go back to the 225 tires on the front. I know the 255 will remain my rear tire size.