Just got mini, and it does frustrate me to not have spare. I look back at the times I have had flats and the tire has either been destroyed, and/or I needed to go more than a few miles to get it replaced.

Therefore, did bunches of NAM searches, and even got the info to place order for the donuts, tray, etc. (Mini of Morristown, mini mania, etc)

But one thing that I coundn't find in my search was the discussion of whether or not its ok to drive with a wheel of a smaller circumference than the other. This was brought up to me by my parts department at my dealership. They said it unsafe and that I shouldn't do it. I did a check the 205/45/R17 have a 10" larger circumference than the donut.

All the other post I have seen have said you only get the donut if you have non-runflats. But from what I could gather, those that have the donut, also have have the smaller stock tires.

So, is it normal for a donut to be smaller than the rest of the tires? and will it damage the car if I use it. I know that it will only ever be used on back tire cause of the breaks.

 

It has been discussed in other threads, do a search, that if you have a front flat you should place one of the rear tires on the front and put the donut on the rear...

Clint

 

I doubt that the donut spare would even fit over the front brakes of a Cooper S. Swap a rear tire to the front & put the donut on the rear. A bit more work, but at least it will keep you motoring. You are fortunate that you have a Clubbie & have room for the donut in the back.

 

If you do not have any kind of limited slip differential, you can use a temporary spare on the front but understand that you really only want to drive at slow speeds (no highway or freeway) and also know that braking and handling will be adversely affected. In other words, if you're around town and just need to get the car to the tire shop for a repair (and you don't have limited slip of any kind), you can put it on the front and drive slowly and cautiously to the shop. If you have to go a longer distance or travel at higher speeds (up to the 50 mph max), then put the spare on the rear and put the rear tire on the front.

 

Good point about brake clearance. You'll know if it doesn't work when you try to put it on.

 

If you have LSD and a flat in the front, you should not drive the car with the "flat" run flats as the LSD will grind, making a horrible noise. Thats what happened to me. I had to stop on the side of the road and call AAA for a tow.

I was told my the Mini techician that the Mini donut will not fit on R56 MCS fronts. But I have not tired it.

 

The donut is for short distances only as is normally stated in the manual or sometimes on the wheel itself.

As for damaging the car? No it will not unless there is an interference issue which you should not have with the stock replacement donut.

If the dealer is telling you it will damage the car I would ask them what they think it will damage. Sounds bogus to me. Remember there is always someone with a strange perception of things they cannot quantify. This is what I try to tell myself when I read wacky stuff on the web or crazy people tell me what they think.

 

I just ordered and installed a mini roof rack and yakima basket and my spare is going up there as I just went to runflats. People look at the car like I'm nuts....they are right

 

I did a search and review of many threads before I posted , and lot of discussion on how to get, why you might need one, and the issue with front brakes.

So I am fine with having to switch the back tires to front as many have confirmed that the donut will not fit on front.

But as goingforspeed picked up, my question relates to the fact the wheels will be spinning at two different speeds. I have not idea how rear axels work and if the "rear differential?" makes it ok to drive. LOL, I have no idea what that means, I heard it on the news or something.

 

There is no rear differential as there is no power going to the rear wheels. The two axles in the rear are just stubs on the end of the suspension bits. You could put any two size tires on the rear and it wouldn't damage the car. (Provided they fit.)

As for the front, if the spare did fit and you had a LSD, then you still would not want to put the spare on the front. Because the tires would be different diameters and turning at different speeds, the LSD would be fighting this speed differential the entire time it was running and you could conceivably wear out or damage the LSD. The LSD is designed for intermittent use, not full time engagement.

 

thanks, for the input, going to see about ordering, and spend a few more dollars on the new toy.