How do you figure out the sidewall strength of a tire?

[Jared at Pelican Parts]

Figured i'd post this here...

I need to get some new tires for my BMW, I'm currently running Sumitomo HTR 200's which i hate as they have NO sidewall support and the car now feels like I'm driving through mud all the time...

I've been VERY happy with the Bridgestone RE750's on my 911SC, and was wondering if anyone knows how to rate a tire based on sidewall strength. Tire Rack doesnt seem to have any info on this..

Anyone have any suggestions for a good tire in a 14" size? I was thinking about the Bridgestone RE950's, any info?

[RallyJon]

A good rule of thumb is that a heavier tire has stiffer sidewalls. It's not perfect, but between two tires of the same size, it works pretty well.

[chibone_914]

Hey Jared, All tires have a "build rating" Back in the 80's this was more commonly known as a "speed rating" "H" rated tires typically don't have as much sidewall support built into it as the same sized "V" or "Z" rated tire.

[Jared at Pelican Parts]

didnt realize the speed rating had to do with the sidewalls.

[RallyJon]

didnt realize the speed rating had to do with the sidewalls.

These days it doesn't. There are plenty of Z rated luxury performance tires that have very soft sidewalls. In fact, as more mainstream cars require low profile high speed rated tires, the manufacturers have made them much softer.

Tires like the Toyo T1S, Michelin PS2, etc have high speed ratings and squishy turn-in.

[Noel]

Someone once told me that the load rating indicated the firmess of the sidewalls. I don't but it though.

The best way to find out IMO, is the read the reviews in Tirerack.com

[Jared at Pelican Parts]

Originally posted by Noel

The best way to find out IMO, is the read the reviews in Tirerack.com

Uh, Im asking here, because Tire Rack doesnt have reviews of it

[RarlyL8]

Application will dictate side wall strenghth.
A "drag radial" is used for drag racing and will have a soft sidewall. A "performance summer" tire will have a stiff sidewall. You can also calculate sidewall hieght via the aspect ratio. A smaller sidewall hieght accompanied with the proper tire use description should get you what you desire.

[Jared at Pelican Parts]

yeah, but I have a 14 inch rim. Hence, it's difficult to find a tire with a small sidewall. ABout as small as i can go is 60

[kycarguy 935]

I found this website that explains some about sidewall strength. It answered a few questions I had also. Hope it helps.

http://www.mazda6tech.com/articles/suspension/are-wider-tires-better-.html

[RallyJon]

195/60-14 Falken Azenis RT215. About as stiff a sidewall as you can find in a street tire. $47 at www.edgeracing.com

[dvkk]

You can ask the guy who's job it is to put tires on the wheels. When I bought my first Dunlop D40-M2s 10 years ago, the tire guy mentioned how difficult it was to get the tire over the rim, the sidewalls were so stiff. Then a couple of months ago when a friend was mounting a pair of Dunlop Sport 8000s for me he made the same comment.

I found it interesting that 2 different tire guys would make the same observation about virtually the same tire.

[masraum]

Originally posted by Jared Fenton
Figured i'd post this here...


I've been VERY happy with the Bridgestone RE750's on my 911SC, and was wondering if anyone knows how to rate a tire based on sidewall strength. Tire Rack doesnt seem to have any info on this..

Anyone have any suggestions for a good tire in a 14" size? I was thinking about the Bridgestone RE950's, any info?

My experience is that the only thing that determines sidewall stiffness is how the manufacturer made the tire. Speed rating and load rating, as far as I'm concerned have nothing to do with it. You can get two tires of different manufacture with the same speed rating, size, and load rating that feel completely different.

I had the RE 730's and RE 750's on my '88 in the stock 16" sizes and thought they felt pretty firm. More so than my old Dunlop SP9000's. I'd recommend them.

As was stated, Toyo T1S's are great tires with lots of stick and high speed rating, but the sidewalls are really soft. It's kind of weird. I don't really care for it much, but the tires stick really well despite how they feel so...

Toyo's are good tires in 14", you may also want to check Yokohama ES100's, Dunlop SP8000's, and Falken Azenis, depending upon the size that you are looking for.

[masraum]

Oh, and to address your thread subject...

ask people who drive performance tires and ask them their opinion. Ask lots of guys because not everyone will agree. If the majority of people say a tire is stiff or soft then there you go. If you are curious about 14" tires ask miata people since older miatae came stock with 14" wheels and miata people are serious about driving. Since like you say, it's hard to find hi-po tires for 14" wheels the miata people have their hand on the pulse of hi-po 14" tires. The main difference is that most miata people will be looking for 55 or 50 series instead of 60. Like I run a 195 55 14 on mine.

[Jared at Pelican Parts]

I've just heard that the BF Goodrich Traction T/A H has a good sidewall in a 14" size. Any comments?

Keep in mind that the BMW is just a daily driver, Cheap is good.

[Noel]

Originally posted by Jared Fenton
Uh, Im asking here, because Tire Rack doesnt have reviews of it

Only 952 people responded to post reviews of this tire, so that may not be enough information for you to make a decision.

Customer Reviews of the RE950 from Tirerack.com

There are also tire comparision tests that Tirerack performed with the RE550:

Link to tire tests

[azasadny]

I was just talking about this with another Pelican the other day. My Dunlop Sport 9000's seemed to have a very soft sidewall and I had many flats cause by nails, screws, etc... stuck in the sidewall. My Bridgestone Potenza RE950's seems to have a much stiffer sidewall and the tire mounter said the same thing.