Originally Posted by shropshiremini View Post
I looked in the manual for my Cooper D and there is even an illustration of Mini with a spare tyre slung underneath. Has anyone worked out how to do this ?
You have to order this option from the factory - which is what I did. What it means is that when my OEM runflats have worn out I can change to standard tyres and not have a problem because I will have the space saver spare wheel if one of the normal tyres suffers a puncture.
Retrofitting this option might be difficult as the boot floor might be different due to the lowering mechanism that exists when you order this option.
There are some quite amusing comments on this thread which show a poor lack of knowledge on tyres in general particularly from tyre fitters.
Runflat tyres essentially have very stiff sidewalls which allow the tyre to still support the cars weight for a limited mileage when they are deflated. As such it means that compared to a normal tyre , their ride particularly in areas of bump absorbance and shock transmission to the suspension will be worse than a conventional tyre. This stiffness also limits the type of rubber compound that the tyre manufacturer can use to make runflats and this largely explains why runflats generally don't perform very well in wet conditions because the tyre manufacturer cannot use the softer grippier compounds on runflats. So the statements about damaging your suspension or engine or gearbox if you change from runflats to normal tyres is complete rubbish. In reality, due to the more compliant nature of conventional tyres, your suspension in particularly will suffer less wear and tear.
Most damage to alloy wheels on the Mini will come from kerbing - neither runflats or conventional tyres will protect you from this and both perform the same in this respect.
Hitting a pothole that is likely to damage your alloy is bad news all round. In this respect converntional tyres have the edge over runflats as it is cheaper to replace a damaged alloy than have to replace parts of the suspension and reallign afterwards.
Runflats have much the same repair characteristics as normal tyres in terms of what area of the tyre can be repaired and size of puncture hole repairable. The only added complication with runflats is that once you have run then for some distance when deflated then the sidewalls will have begun to deteriorate and consequently it is not really safe to have then repaired. This deterioration is why you cannot run runflats deflated all the time - typically the limit seems to be around a 100 miles or so depending on car weight/occupancy.