[beegeema]

Hi Guys,
There was concern in this forum about 205/50-R17 tires having clearance issues when married with a stock OEM Cooper-S. I just installed on my Stock OEM 17" R85 S-spoke rims - 205/50-ZR17 A/S Avon Tech M550 All-Season conventional non-run flat tires. After physical inspection as well as 100 miles of city/highway driving I have found absolutely no clearance problems with this size tire. I am also experiencing exceptional handling, good road grip (I do not, however, push the car to its limits), as well as a much improved ride over the rock hard run-flats. With the extra 0.40 inches of softer cushion between the rim and the road there is a world of difference - the harshness is history. I also look forward to improved traction in snow. I may choose to go with an extra set of rims (15" or 16") with a narrower footprint dedicated conventional snow tire for winter driving here in New England. For now I'm quite pleased!

It seems that no one has listed this size tire in their profile. I just wanted to temper any hesitation someone may have about going with a 205/50 over the stock 205/45. I at least am having no problems with clearance and foresee none. - Enjoy Thanksgiving -

[Mike Edwards]

The extra sidewall height will have raised the gearing and - more important - made your speedometer under-read.

Hence, why people are trying tire sizes that retain the same sidewall height as the standard tyres.

[beegeema]

Thanks Mike for your input - I do understand the following:
205/45-17 stock OEM tire's diameter = 24.2638" and circumference = 76.227"
205/50-17 replacemnt tire's diameter = 25.0709" and circumference = 78.762"

It's a 3.33 % increase in circumference with the 50 aspect ratio tire over the stock 45 tire.
This does mean that the speedometer as well as odometer will be off by that 3.33%.
If the speedometer is reading 60 mph - I'll actually be going about 62 mph.
If the odometer reads a change of 1 mile - I'll actually have traveled about 1.03 miles.

I knew these would be off but, until I just did the math, I didn't know by exactly how much. The speedometer & odometer offsets - to me - are acceptable trade-offs for ride comfort since my wife is now taking over the Mini and is demanding comfort.

I have an apointment at my Mini dealer on Friday since they said the onboard computer will need "re-calibration" due the change to non-run flats. Can they also re-calibrate the computer to compensate for the increase in tire diameter as well - correcting the speedometer and odometer readouts?

Also, when using a 205/50-17 tire, the radius from the axle to the pavement is increased from 12.132" to 12.535". That's a 0.4" increase. Does this mean that the wheels will require re-alignment since the dimension increases are slightly greater (+3.33%) than the acceptable +3.0% variance from Mini's OEM specs?

Thanks in advance for any further thoughts ... Brent

[MINIAC]

Quote: Originally Posted by beegeema

It seems that no one has listed this size tire in their profile. I just wanted to temper any hesitation someone may have about going with a 205/50 over the stock 205/45. I at least am having no problems and foresee none.

No one has reported running 205/50-17 because this fitment is NOT performance oriented

While increasing the sidewall height provides more ride comfort and it makes for slower acceleration

[beegeema]

Hi Miniac - Thanks for your input as well. My wife's not 'perfomance' oriented so that's a plus. I do have the nagging question about the re-alignment issue noted in my last edited post. I'd appreciate any thoughts you might have.

[MINIAC]

Quote: Originally Posted by beegeema

I do have the nagging question about the re-alignment issue noted in my last edited post. I'd appreciate any thoughts you might have.

I don't think you need a realignment, but I'd call Tire Rack and ask them.

[MiniE]

anyone run 205/50/17 with lowering spring?