Having ordered my spare wheel and tyre for my Fiesta Titanium I picked it up from my local Ford dealer, (By the way if your car has not been supplied with a spare wheel you also require a jack and a retaining screw for the boot to hold the wheel in place) the tyre size was 175/65 R14 but the tyres on my car are 195/45 R16, when I phoned the dealer up they said that the spare was the right size, could someone please explain if I have the correct spare wheel size. Many thanks.

Regardless of what wheels you have, the spare will be the same size. It's very common to have the spare smaller, that's why mileage should be as limited as possible on your spare.

Right the 175 on a tyre number refers to the width of the tyre in 175mm and this is less than the standard 195 as Fords, I assume, have decided this will mean they can design a smaller spare wheel compartment at the bottom of the boot (i.e. the floor doesn't need to drop out of the bottom of the boot as much as it would with a 195mm tyre, only an inch or so I know but ... anyway this leaves the designers more space to plan where the exhaust etc can go, or plan where the wheel brace etc will sit)

The /65 relates to the height of the tyre sidewall expressed as a percentage of the tyre’s width (i.e. from the the top of the rim to the tread) and is quoted as a percentage i.e. 65%, whereas the standard alloy wheel / tyre is more low profile as its /45 so its only 45% and thus looks better and more sporty

A 16 inch wheel = a diameter of 16 x 25.4 (inches to millimetre conversion) = 406.60mm

/45 of a 195 tyre = 195 x 0.45 = 87.75mm (this needs to be added twice as the tyre is above and below the wheel rim)

So the overall rolling circumference of ya standard alloy wheel / tyre combo = 406.60 + 87.75 + 87.75 = 582.10mm

A 14 inch wheel = a diameter of 14 x 25.4 = 355.60mm

/65 of a 175 tyre = 175 x 0.65 = 113.75mm

So the overall rolling circumference of ya steel spare wheel / tyre combo = 355.60 + 113.75 + 113.75 = 583.10mm

Anyway, if my maths is correct this is within 1.0mm of the standard alloy wheel / tyre combo. You shouldn't notice this when driving - however the width of the tyre is less, 175mm not 195mm, so you should take care getting home and that is the point of these types of spares, its just to get you home. This also allows the Manufacturer to supply you with a cheaper steel wheel with a non-low profile tyre and still allow you to get home

Don't worry it won't make the car tip at one corner as you might of imagined when you first see that its a 14 inch wheel ................

Was the spare a steel not an alloy ?? - What was the make of tyre (purely out of interest ??)

I have 16" alloys and my spare wheel is 14" so I think it is normal:)