Having heard years of tyre industry comments about the problems encountered in fitting runflat (RFT) and ultra low profile tyres (Lo Pro’s) and the frequency of damage, to both the tyre and alloy wheels, The Campaign for Better Tyres resolved to research the exact nature of the problem and any solutions available.
Anecdotal tyre shop talk confirmed that fitting RFTs and Lo Pro’s is difficult and requires skill and experience even when using modern helper arm tyre changers and ultra difficult when performed on conventional tyre changers. A lot of minor damage to customers tyres and rims was reported but the tyres are still fitted and the customer is told nothing about it. As in many situations like this, it is hard to substantiate and quantify the extent of the problem as the feedback was highly subjective and lacked documentation.
Then Better Tyres tracked down a copy of a major German Court mandated official investigation by the international Rema tyre technology company. Back in 2006, Rema became concerned about numerous reports concerning damage to RFTs. Rema commenced an evaluation assignment to appraise the extent of the problem and possible causes. As the examination progressed, there was increasing suspicion the damage to RFTs was caused during the mounting of these tyres on rims. A sample of 50 RFTs were examined and most of them were found to have what was assumed to be mounting and removal damage. Damage to these tyres included traction grazes at the point of mounting and beads that were broken, squashed and ripped, bead heal damage, and beads worn down despite the use of lubricant paste.
In association with Darmstadt University, Michael Immler, the German Court appointed expert witness for the Vulcanizer and Tyre Mechanic Trade was commissioned to conduct exhaustive tests on more that 220 new tyres and 100 second hand tyres with over 3500 mounting operations.
The expert witness concluded design of rim, design of tyre, design of tyre changer including tools and accessories (including tyre paste), temperature of tyre and tyre shop and the fitters skill were all variables responsible for the successful and damage free mounting of RFTs. If only one of the variables is NOT within specification, damage to a tyre during mounting or removal is VERY likely.
By far the most crucial variables are operator skill and the type of tyre changer used. For sure, there is no subsititute for operator experience, training and skill but even this is reliant on the use of the appropriate tyre changing technology.
When fitting or removing RFT’s and Lo Pro’s, there is no substitute for use of modern leverless tyre changers being the only way to reliably fit/remove these tyres without damaging the tyre or the alloy rim. Conventional tyre changers are almost guaranteed to damage these tyres and rims and even modern help arm tyre changers are liable to damage tyres with a high frequency.
The Campaign for Better Tyres recommends drivers protect their Runflat, Ultra Low Profile tyres, expensive alloy rims and safety by insisting their tyres are only worked on by tyre shops with leverless tyre changing technology; otherwise there is a high chance of damage.