R95 - JCW Star Spoke RIMS come standard with a 205/40-R18. What is the maximum tire size I can go with on the R56 (with JCW Aero Kit)?

 

205/40-18 is the stock size and good for runflats. Fits rims 7-8" wide.
You can also find some good tires as well in this size-
Michelin Pilot Sport PS2 $218 each 20 lbs 220 treadwear
http://www.tirerack.com/tires/tires....4YR8SPORTPS2XL


If you want non runflats you just want the tire to fit the rim width and be in the 205 to 225 mm width range with tire diameter of about 24.4".

R95 wheels are 18x7" with +52mm offset

215/35-18 fits rims 7-8.5", perfect for 7.5" rim 23.9" tire diameter
225/35-18 fits rims 7.5-9", perfect for 8" rim 24.3" tire diameter
215/40-18 fits rims 7-8.5", perfect for 7.5" rim 24.7" tire diameter

So besides 205/40-18
you can choose
215/35-18 or 215/40-18

Tire selection will vary with the different sizes, not all tires are made in all sizes.

What tires were you thinking of?

Do you have any snow?
Do you have wet weather?
How are your priorities? What is more important: Handling, comfort, budget, treadlife?

 

BFG G Force or Conti Extreme Conti
Snow is minimal I live in Atlanta, GA.,
Rain can be a problem when we get it. We have been in a drought lately.
I like the handling and treadlife. However, I am not racing (wish I was) and its mostly daily commute.
I want a tire that has a little more section height and width. So I guess I will try and go with the 215/40/18. Are their any brands you recommend! I don't beleive the Conti's come in that size. Thanks for all of your help. Its greatly apppreciated.

 

Thinking of changing from run-flats to non run-flats. I have 18' R105 JCWs on the MINI. Will 225/40-18 fit? FYI --- car is not lowered.

 

Thinking of changing from run-flats to non run-flats. I have 18' R105 JCWs on the MINI. Will 225/40-18 fit? FYI --- car is not lowered.

 

Here is a great tool to figure out alternate sizes: http://www.miata.net/garage/tirecalcold.html Once you have that figured out, it's a matter of what will fit the wheel correctly. A 235/35/18 is almost exactly the same size as a 205/40/18, but will it fit the wheel and will it not rub?

 

You have 18x7" rims

225/40-18 fits rims 7.5 to 9" wide, perfect fit for 8" wide rims and has a tall 25.1" tire diameter which about 0.7" tall. If you have an R56 MINI and stock suspension you can probably get it to fit but the tire is too wide for the wheel and too tall for the MINI in terms of design vs stock. You get less clearance and more chance for rubbing under load and it will look oversized for the rim and car with increased ride height. If you have a R53 MINI then it's not a good size to run for street use. Running wide tires on narrow rims can stress the sidewalls more.



235/35-18 fits rims 8 to 9.5" wide, perfect fit for 8.5" wide wheel, and has tire diameter of 24.5". It is too wide for an 18x7" wheel although you can force it to mount. It will look too wide and tend to overstress the sidewalls especially under load.

See post #2 for correct options on tire sizes. Or talk to Alex@tirerack.com extention 294.