AveoNetwork.com Archive -- on AveoForum.com

so whats a good tire size for R15s that wont make too much of a difference on the speedo?

a 195/50r15 is .3% off. That means it will read "correctly" at speed.

When you are going 100mph on your speedo, you will be going pretty much 100mph. the speedo is off more than the tires.

cool thanks
how thin r the 195/50s?

thin? the are 10mm wider than stock on the tread. the side wall is 97.5mm with is just over 3 3/4" So basically it is 1/2 less sidewall..

Haha that site says if we put 28s with 95 profile we have to do 31.4 mph to do 60 mph that's pretty halarious. But thanks rabbit on that will definately come in handy.

Incase anyone doesn't know... sorry if this is just restating the obvious...

Tires size works like this:

"185/60" /14 =

"185" is how wide the tire tread is going to be... so this tire is narrower than a 205 but wider than a 175. I think this is in millimeters.

The '60' means the sidewall is going to = 60% of the 1st number, in this case 60% of the 185 tread width.

A 185/65 would be the same width just taller as the sidewall is 65% of the 185.

a 205/ 65 would be wider AND taller since 65% of 205 is greater than 65% of 185.

So Generally speaking, you can think of tire sidewall height like this:
(from tallest to shortest-regardless of width):

80 series- basic economy and ride comfort, snow tires/ all seasons.
70 series- touring , sport touring, all season.
60 series- sport touring. performance all season/ in lower 50 states. high performance on heavier vehicles.
50 series- performance. low profile, for larger wheels.
40 series, ultra high performance, very low profile. for very large wheels

And width: (from narrow to wide- side wall height (series#) can have an impact on performance):

165 width. looks very narrow. economy, or RWD drag racer front tires
185 width. Touring. doesnt usually look wide. M+S / all season.
205 - getting better. looks a little beefy.
215. looks nice and wide especially on a smaller vehicle
225. a pretty wide tire for a standard FWD vehicle. Standard Wide performance tire on a performance FWD or RWD.
235 gettin very wide and grippy.
245..better have some serious wheel wells or fender flares and horsepower.

just watch those descriptions on the end. a 40 series isn't always less sidewall than a 60 series.. that generality depends on the width of the tire being the same.

Also, those widths are good, but beyond a 215 on our cars will rub. plus the increase in performance of the contact patch is only beneficial with the hp to back it up. the grip and handling still improve, but if you don't have the power to move more tire that is touching the ground, you will be "slower"

Yeah, my wheel still spins during pick up from stationary. Screeh like mad. 210Nm on wheel is too much for the 205mm tyres to handle.

i need to change to better tyres.

it might not just be the 205 tires, you might need a softer (stickier) compound.

I like 205 and 215 series Bridgestone Potenza tires...very sticky. I have Potenza GRIDs for my 17's, but Im gonna run the stock Kuhmo 14's for the winter just to get some miles out of them...otherwise I'll never use them.