Why the f00k does my sidewall keep bubbling?

[JackEatsEmoKids]

Yes, I understand that. However, 40% of 255 is always going to be 102mm.

Width x Aspect Ratio = Section Height
Section Height x 2 = Combined Section Height
Combined Section Height + Wheel Diameter = Tire Diameter

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=7

255 x .4 = 102mm = Section Height
102 x 2 = 204mm = Combined section Height
204mm + 431.8 (17 x 25.4) = 635.8 / 25.4 = 25.0314 inch = Tire Diameter

Falken 512's list a 255/40/17 as a 25.2 Diameter. (A tire that people consider "small")
Falken 452's list a 255/40/17 as a 25.0 Diameter. (A tire that people consider "small")
Falken Azenis RT-615 list a 255/40/17 as a 25.0 Diameter (A tire that people consider "correct"/"big")

Your examples:
Toyo RA1 lists a 255/40/17 as 25.0 Diameter. http://toyotires.com/tire/pattern/proxes-ra1
Toyo TR1 lists a 255/40/17 as a 25.0 Diameter. http://toyotires.com/tire/pattern/proxes-t1r


Those are all measured on a 9" wide wheel by Falken and Toyo.

That's a variance of +/- .2" (.1" top and .1" bottom). That's acceptable, but I cannot see any tire have a +/- .5" variance in measurement...

Again, it's all visual differences. Math and numbers don't change.

What I mean by running small, is a 235/45-17 Falken ZE512 stretched on my OEM 17x8's while the Toyo Proxes4's I had in the same size were squared in the same rim. The rolling diameter looked smaller by a cunt hair though.

[Han]

What I mean by running small, is a 235/45-17 Falken ZE512 stretched on my OEM 17x8's while the Toyo Proxes4's I had in the same size were squared in the same rim. The rolling diameter looked smaller by a cunt hair though.

Although, I know what you mean, it's only a visual appearance. The way the 512s are designed look stretched even on stock wheels and tires. There are extremely minuscule differences in rolling diameter from tire to tire, but it's acceptable. (Nothing that will make or break a "size," since a 225/40/18 is a 225/40/18 mathematically). I have no argument there on the visual point of view, but on a math side, it's all the same.

[geoffafa]

whoa this thread has somewhat derailed, but in a great way.

all this info is great to know. Im gonna look into the nittos (a friend has some 225/35/19 on some 8.5s in his a4. he loves them. Ill also look into the nankangs.

but can anyone give me feedback on the hankook rs2?

[da_force]

I'll go back a bit...

All in all what do you guys think of T1R's in 205/40 on an 17x8.5 rim?

[Polo Classic]

Ok so this all started on my old set of wheels, I had 19x8.5 with a set of falken fk452 225/35 on them, i noticed after about 5 k my sidewall bubbled on both fronts. I put them on the back and put the good tires up front, which also lasted me about another 5k.So my question to you all is, wtf am i doing wrong?

Is this a result of an impact? or lack of checking tire pressure? or do i officially have the worst luck in the world?

fuck sorry for the book guys... but i appriciate any help.

What tyre pressure are you running. Whats the load index of the tyres and what does the car weight (f/r)

I'd say most likey the 225/35 and 205/40 have a too low load rating for your Audi

(running 235/30-20 FK452's on 9,5x20)

[Neb]

I've ran Nitto Neogens and loved them. they stretch great and handled good for the tire.

Also had Fuzion Tires and I liked them a lot.