Tire question

[kyleag89]

Will 33x12.5-15 tires fit on my AR 15x7 rims?

[mvusse]

You can make it fit, but IMO 7" is too narrow. For a 12.5" wide tire I suggest a 10" rim for street use, or 8" for off road.

 

Suggested minimum rim width according to tire manufacturer is usually 8.5".

 

A 33x10.50 will be fine, though.

[mnkyboy]

Yes they will fit,15x8 would be better though

[kyleag89]

I might have 15x8s.. I'm not sure. I have AR Baja chrome wheels with 31x10.50 tires now and the tread sits flat across, but they are almost shot. I bought the jeep with the wheels on them and there are no markings visible.

 

EDIT they are Mickey Thompson classic 2s. I went to there website and they only make 15x8 15". So a 12.5" tire would be ok for them?

[mvusse]

Yes, but just barely.

[kyleag89]

Ok thanks guys. I actually just found a set of 31s mounted on D window steelies for 350 so I think I will pick those up tomorrow and sell mine.

[91coMANche]

Yes, but just barely.

 

A 12.5 tire is perfect on a 8" wide wheel. If you go any wider you'll debead so easily. Now in the 1980's you wouldn't run a 12.5" wide tire on anything less than a 10" wheel :brows:

[mvusse]

Yes, for off road. But on the road the tread bulges too much and the outside edges of the tread will not make contact, causing faster uneven wear unless you air them down at the cost of higher fuel consumption and even faster wear plus the risk of a blow out.

 

It is for these reasons I have my $1200 35x12.50 play tires on 8" rims, but my $100 33x12.50 road tires are on 10" rims.

[Eagle]

Yes, for off road. But on the road the tread bulges too much and the outside edges of the tread will not make contact, causing faster uneven wear unless you air them down at the cost of higher fuel consumption and even faster wear plus the risk of a blow out.

 

It is for these reasons I have my $1200 35x12.50 play tires on 8" rims, but my $100 33x12.50 road tires are on 10" rims.

:agree:

 

Cooper tire recommends an 8-1/2" rim for 10.50s and a 10" rim for 12.50s.

[jpnjim]

Some 33x12.5's fit OK on 7" wheels.

 

Some 33x12.5's fit horribly on 7's.

 

 

 

It's all what the tire was engineered for.

 

When they design a tire,

it's engineered for a specific bead spacing.

Hopefully with a little wiggle room above, or below that number.

 

 

 

 

Original style Bias 33x12.5-15" TSL's are a great example.

 

In reality, they're under 12" wide,

but their casing was engineered around a 15x10" wheel.

 

 

Put them on a 15x8 (like I, and everyone else has),

and they crown worse than most 12.5's do on a 7".

 

It's not just a bias ply thing, since Bias TSL Q78's are only about 1" narrower,

but fit on 15x6's like a glove,

 

That casting was engineered to fit 6's.

 

 

 

 

 

 

Reminds me of the sticky Dunlops that were on my first GSXR (motorcycle).

 

In 1986 the most common track bike on the planet (GSXR750) came with

narrow 18"x3.5" rear wheels & skinny (5.5") 140/70-18 tires.

 

Wider 150's & 160's were designed for 4 & 4.5" wheels,

and were a poor fit on the GSXR's narrow wheels.

 

 

Dunlop stepped in with a huge (for the time) 6.6" wide 170/60-18 DOT sticky designed around those narrow little 3.5" hoops.

They had to compromise sidewall angle (flatter is normally better for stability),

but they were able to design in the tread profile, and width they needed, even with the huge disparity in tire vs wheel width.

 

 

 

 

So,

I have no doubt a 33x12.5" could be designed fit a 7" wheel,

just like they could design one around a 12".

 

 

Seems like most are spec'd for a 10-8.5" wheel, and going outside of that is a compromise. :smart:

[jpnjim]

FWIW,

the closest I've ever seen to a manufacturer allowing their 33x12.5's to be run on 15x7's is here:

 

 

 

Those factory sponsored Jeeps,

with factory sponsored Goodyear tires

ran 33x12.5-15's on 15x7" wheels.