Can anyone tell me the revs per mi on a tire 285/65/r18 so i can adjust me x3.

Thanks

 

Go here, there is a calculator.
www.discounttire.com

 

Green,

You could also look at the tire manufacturers website. Several, if not all, have that information listed for your tire. However, I am running into a problem with my Toyo 285/75 R18. The toyo website says 597 while the discount tire and other websites I have tried are giving me 579. My Speedometer (and I guess odometer) are off so I may try to set mine for the 579 setting. Good Luck.

 

What is your radius in inches from the ground to the center of your axle?

 

Never really measured it but Toyo says the tire is a 35x11.something so I would say its 17.5" off the top of my head. Green, sorry for the quasi hi-jack.

 

Loaded radius; the tire on the ground.

 

Yep, the sqish factor. That may be the reason his speedometer was off.

 

How to find your revs/per mile:

Formula:
x = The loaded tire radius in INCHES from ground to center of axle.
63360 / ( 2 * pi * x )

Example:
63360 / ( 2 * pi * 16.5 )
(copy/paste in google search bar)

Answer:
63 360 / (2 * pi * 16.5) = 611.154981

The sqish factor it is.

PS: My most constructive post for a long time.

 

[QUOTE=i.ride.suzuki;3389982]How to find your revs/per mile:

Formula:
x = The loaded tire radius in INCHES from ground to center of axle.
63360 / ( 2 * pi * x )

Example:
63360 / ( 2 * pi * 16.5 )
(copy/paste in google search bar)

Answer:
63 360 / (2 * pi * 16.5) = 611.154981



The sqish factor it is.

PS: My most constructive post for a long time.[/QUOTE]

Don't you feel better!

 

[QUOTE=bluejay432000;3390216]OK HONESTLY THAT ALL LOOKS LIKE JIBBERISH TO ME. SORRY IM AN IDIOT! IS THE 611 RIGHT FOR MY TIRE? I LOOKED IT UP ON A CACULATOR ON THE INTERNET AND DISCOUNT TIRE AND IT SAYS 640, BUT THAT SEEMS WAY WAY OFF. SO I DONT KNOW

 

[QUOTE=Green_Machine;3392906]Go with the 611 in the above calculation. If you use the Discount Tire site, you still need to deduct 3% to 5 % for the squish factor. A 5% reduction would put you right at 611. If you have a GPS, check it to see how accurate it is.

 

^^

Alittle off topic but I can't remember. What size is the 33 x 12.50, 305 / 65?

 

[QUOTE=bluejay432000;3392923]OK, ILL TRY THE 611. I DONT HAVE GPS, BUT RIGHT NOW I AM 5 MPH SLOW (SHOWING) THAN WAHT I AM ACTUALLY RUNNING. SO IT SHOWS 50 BUT RUNNING 55. I JUDGE IT BY MY UNCLES 01 F-150 WHOS IS BONE STOCK. ILL SET IT TO 611 AND LET YUO KNOW HOW T FEELS. THANKS

 

I don't know the answer, but the Discount Tire site has a conversion chart.

 

[QUOTE=bluejay432000;3392923]THE X3 DOESNT HAVE A 611, SO I SET IT ON 610.