In search of runflat tyres

HELPDESK:Answering all your motoring queries

From AS:

I have a BMW 318 SE with runflat tyres. The last time I replaced one – due to wear – I had to wait a week for delivery (I live in Letterkenny). I am concerned that should I have a flat that can’t be repaired, the car could be out of action for a week. Are these tyres easily available? Can one switch to ordinary tyres? (I realise that will have implication for where the spare goes). If I did switch, can I mix runflats with ordinary tyres?

I’m assured that runflats are readily available. Bridgestone, for example, has a next-day delivery service nationwide. BMW also claims all its dealerships receive overnight deliveries of tyres. And remember, the whole purpose of runflats is that you can still drive on them, albeit at reduced speeds and limited distance. Check the car’s handbook for the recommended speed and distance limits, but it will get you to work and back if you get a puncture. Many can achieve hundreds of kilometres at speeds up to 80km/h.

I’d be very wary of changing to ordinary tyres as the car is designed for runflats and such a move would compromise suspension, ride and handling.

I certainly wouldn’t mix ordinary and runflats. Indeed, a BMW spokeswoman tells us that “mixing conventional tyres and runflat tyres should never been done. The reason for this is that there is more movement in the side walls of conventional tyres, so mixing tyres would significantly change the behaviour and character of the car.”

In short, if your tyre supplier can’t get you a replacement quickly, go to another supplier.

Send your queries to Motors Helpdesk, The Irish Times, Tara St, Dublin 2 or email motorshelp@irishtimes.com