On this forum (also at Mini2), the question frequently comes up, "I am considering this wheel-tire combination and it has rim size aaxbb, offset cc, and tire size ddd-ee-ff. Will there be rubbing issues?" I myself will have this question when I swap out OEM wheels and run-flats.

Is there a simple way to check whether a certain combination might cause a rubbing problem? It could be a mathematical formula or even something as basic as a list of dimension combinations that are known to work or not work.

 

Tolerance is usually a factor especially on tires...their widths of 205 could
be 205 to 210 depending on where you measure the width (shoulder or
end of tread, etc).

For instance a 205 on SP9000's is narrower than 205 on AzenisSport or
GS-D3, S03's.... a 205 is narrower if 45 profile over 50 profile. wrapping
them on narrow or wide wheels also have effect.

Typically max offset would be +42 if running wide shoulder tires...but
it's trial and error when it comes to it at the end.

 

rkw,
If you have stock suspension (MCS or MC) then you can look for:

Rims like-
15x5.5" to as wide as 15x7"
16x6.5" to 16x7.5"
17x7" to 17x8"
18x7" to 18x8"
20" rims (see tirerack for TIS rims)

Rim specs-
4x100 bolt pattern
56.1 hub bore or larger (when using 67.1, 73mm or larger bore you can use centering rings to fit the wheel to the MINI hub)
Offsets from about +38mm to +48mm

Tires (common sizes)
205/55-15
205/50-16
205/45-17, 215/45-17, 215/40-17
205/40-18, 215/35-18

Wider tires (less common)
225/50-15
215/45-16, 225/45-16
225/35-18

Look for tires no wider than about 215mm with outer tire diameter about 24 to 24.4" for closest to stock tire fit.

for more info see
http://www.mini2.com/forum/faq.php?f...factory_wheels

For lowered MINIs the clearance with the wheel arches gets harder to predict and often slight rubbing does occur but isn't that bad.

Wheel offsets tend to be more limited about +42mm to +48mm but it does vary.

Also consider if you are planning for a big brake kit later- those don't fit all wheels- more space is needed for the calipers to clear the inside rim edges.

 

minihune, thanks for the information. It will be convenient as a quick reference.

I have some additional questions about wheel offsets. If a wheel is available in several offsets within the Mini's range (e.g. Rota Slipstream available in 35, 40, 45, or 48 mm offset) how should the offset be selected? Is the width of the wheel and tire a factor in choice of offset? For example, if I were considering a wide (215 or 225) tire, should the offset get smaller or larger, or does it matter?

 

In general if the rim is close to the width of the stock rim-
namely 15x5.5 or 6", 16x6.5 or 7", or 17x7 or 7.5" then I try to get very close to the stock offset of roughly +45mm to +48mm whenever possible rather than the opposite direction. The larger the offset number (+48mm) the more the rim is placed into the wheel well or midline of the car. At some point it can rub the suspension components.

As the width of the rim gets even wider then you'd want the offset to be proportionally less to allow some of that wide rim to be placed closer to the outer fender well and hanging towards the outside of the wheel arch but there is a limit to clearance in this area due to the wheel arch design especially when the car is lowered.

So rims as wide or wider than about 15x7, 16x7.5, 17x8 etc might do better with offsets of about +35 to +38mm. There is some variation that will fit.

You can adjust a bit more when running more negative camber front and rear and by having coil overs that allow for adjustment of ride height on each wheel.

When buying from tirerack.com it's best to consult with Alex first. Tirerack allows you to sign in with a given car which then will list various wheels with the correct clearance to fit. There may also exist some wheels that are best suited to other cars (like the Miata) that still might fit the MINI.

For tire width, you should always consider the tire and rim together as a pair. Let's say you are looking at stock 15x5.5" rims and want to add a wider tire. You're looking at 225/50-15 or 225/45-15. You'll see that 205/50-15 fits a narrow 5.5" rim and up to rims that are 7.5" wide.

But in the case of a 225/45-15 tire you'll need a rim that is at least 7" wide to fit the wide tire. So usually you cannot use the stock 15x5.5" rim but be looking for 15x7 or 15x7.5" which also means looking at wheel offsets in the +35 to +38mm range due to the wideness of the rim.

In the case of 225/50-15 tires, it will fit rims of 6 to 8" width with a perfect fit for rims that are 7" wide. A determined mechanic can mount these wide tires on a 5.5" rim but usually this is for a race application. It's a better fit to have 15x7 or 15x7.5" rims for such a wide tire- and appropriately less wheel offset.

When the edge of the rim and bead of the tire fit well, you'll get less wiggle under use,potentially loose less air, wear and stress the bead less, and have better performance.

 

minihune, thanks for another very informative post! I think I have a good understanding now for evaluating wheel and tire specs.

 

Hi per above, am I correct to assume the 225/50-15 on 15x7 with offset of 42 ill fit cooper s lowered about 1/2"?! That would be great..

 

I think it might be close to rubbing a suspension part in the inside of the wheel wells. No rubbing on the plastic outer trim. The 225/50-15 is smaller outer diameter than stock and a 1/2" drop is minimal.

Try calling Alex@tirerack and ask about fitment in your case.

With 15x7" rims and 205/50-15 tires I have rubbed my brake linings before and had to watch for clearance.

 

Great thread on offset and tire/rim size.

It should be considered as a "sticky"

Steve