E30 Zone

I've got a spare wheel with a directional tread pattern on it, so depending on which side I have a flat tyre I could end up having to put it on with the tread in the wrong direction.

So how bad is it to run a tyre with the tread going the wrong way? If I have to run the spare the wrong way I assume I just do it for the minimum time possible until the other wheel is fixed?

if you have to use it dont drive fast!
i think its mainly in the wet you get problems

I have driven on directional tyres in the dry and barely noticed a difference.

But, they are LETHAL in the wet / standing water as the tread pushes all of the water into the centre of the tyre which in turn then pushes water out between the tyre and the road meaning your contact patch is reduced....

The quicker you go / more water there is, the grip will become less and less.

Personally I buy a cheap (non directional) replacement, or just be very very careful!

Fit to the rear,and take care.

As above. It's all about the water displacement. In the dry, you'll be fine, but in the wet, prepare for the ride of your life. That one tyre will feel like it's on ice. I paid £30 for a budget 17" tyre for my spare last week, non directional. Gotta be a couple of quid worth spending to be on the safe side.

I think I might just get a cheapy non directional one for the spare then, don't really like the sound of the lethal wet weather performance.

Cheers

Risk management - average one puncture every five years ... less than 50/50 chance of there being a lot of standing water on that occasion (driving in the rain and standing water are different) .... spare will be on the car half day max .... . Could argue that putting a spare on with the wrong psi is equally risky, how many people check the spare psi every week? Put another tyre on the spare if you feel the need, don't lose any sleep over it if you don't