View Single Post
      02-01-2013, 04:07 AM   #26
Major General

Drives: BMW F11 535i Touring
Join Date: Mar 2007
Location: Scotland, Highland Region

iTrader: (0)

Originally Posted by Gary Whale View Post
Any answers anybody to Irnbrukid's question?
British Tyre Manufacturers’ Association

Repair of SSTs

SSTs have specially reinforced sidewalls to enable them to perform when deflated for a limited distance and at a restricted speed. The distance permitted under these conditions may vary according to the tyre or vehicle manufacturer concerned.

When running in a totally deflated or significantly under-inflated condition the tyre’s internal structure is subjected to high stresses and hence may become weakened and permanently damaged, rendering the tyre unsuitable for repair. Unlike standard tyres, damage symptoms may not be visible with SSTs. As each tyre manufacturer may use different technical solutions to provide run flat capability, the views on repairing of SSTs varies across the industry.

Hence, reference should be made to tyre specialists or to the relevant tyre manufacturer for repair guidelines and to the vehicle owner’s handbook regarding the use of repaired tyres on the vehicle.

Prior to a repair being carried out the tyre must be removed from the wheel and given a thorough internal and external examination by a tyre professional. This is to ensure there is no visible structural damage that may preclude a repair.

The responsibility for the repair remains with the repairer of the tyre.

Also proper puncture repairs should be carried out in accordance with BSAUl59 regulations. Only a vulcanised plug patch should be used, which repairs the tyre to the required standard.

Hence for inspection and a 'plug patch' repair, the run-flat tyre must be removed from the rim.