LUMP on your TYRES How Can One of Your Tyres Develop an EGG on the sidewall?

Why Can One of Your TYRES Develop a LUMP on your TYRES

Most car drivers have seen a  lump on your tyres. These lumps may  appear on one of their tyres at one time or another. The first time that I came across tyre with a bubble was in the early 1970s when radial tyres were becoming more popular and taking over from X-ply tyres. The tyre market was a different world in those days. Most of the large tyre companies were American, the likes of

lump on your tyres

The area that has worn out on this tyre is due to an egg forming but the customer knew nothing about it?

Goodyear and Firestone, with Michelin tyres  representing most of Europe along with Pirelli tyres.

The first radial tyres to come onto the market were mainly textile radials

So, these were radial tyres without any steel belt in the tyres construction. In the early days, Michelin Tyres UK was the only tyre company to have a steel belt in the tyres construction.The first being the famous Michelin X, who soon built up a reputation for the high mileage that their tyres produced. These tyres were renowned for doing 60 and 70 thousand miles, before requiring replacement.

Of course, Michelin’s competitors were far behind !

With the textile radials doing only half the miles . Consequently, the race was on to incorporate a steel belt in their own brands of tyres. I can remember some of the disasters that some of the American tyre companies were having. Of course, in their quest for a steel belt and higher mileage.

In the early days of radials, Firestone had a factory in Liverpool producing car tyres. Subsequently, and went into the production of steel belted radials. The tyres that were made in the American factories were known as the “Firestone 500. But Firestone made one hell of a mistake ? So, building the new steel radials in “bias belted” tyre molds ! This together with the wrong type of steel used in their construction. Caused a production catastrophe ! Causing a massive tyre recall. Due to the  belts separating . Giving their tyres a lump on many of their tyre products.  

Similar problems were experienced in the Liverpool factory.

This was to be the first time that I had experienced a  lump on your tyres also known as a bubble or egg appearing on a tyre. The steel belts that were used were not coated with a protective coating of brass and because of that the steel rusted and caused them to come apart and some of them developed a huge  lump on your tyres tread areas. A similar thing happened at Goodyear tyres. Michelin had kept their formula for the steel wire coating a patented trade secret since 1948 and the next twenty years but eventually they relented and leased out the trade secret to the other tyre companies, but the other companies never overcame Michelin supremacy in the steel belted tyre market.

Remoulders start to make steel belted tyres

Remoulding companies then started to make the steel belted radials, but many of their tyres would fall apart because they were using the wrong type of steel belted casings and once again the tyres began to develop a large lump on your tyres or  eggs or bubbles. This would give the remoulds a bad name for many years to come.

I can remember working for a Goodyear retail outlet at the time and we had to change hundreds of faulty ones  due tyre separation and large  lump on your tyres developing giving the cars a very bumpy ride indeed.

lump on your tyres,michelin tyres

The very first Michelin man (scary)

Eventually all the tyre companies sorted themselves out but at a great financial loss, in fact Firestone lost that much money that they were sold to the Bridgestone company in 1988, who still make the Firestone tyre products to this very day, Car remoulds had got themselves a very bad name and were eventually killed off by the “cheap tyre” imports from China. This

lump on your tyres

This is still the Granddad of all lump on your tyres

reduced the price of a new budget tyre and so it became a false economy to buy remould tyres.

Why do we get LUMP on your TYRES in today’s modern tyres?

The problem of the eggs on your tyres is still with us ! But because of the materials that they are now made from and the hygienic factories that tyres are made in. So the egg on a tyre is now becoming very rare.

The most common cause is that a nail or screw can penetrate the tyre tread. Damaging the protective coating of the steel belt. Of course, this will allow tyre steel to become rusty. Which in time oxidizes and allows oxygen and air to become trapped in the layers. Thus causing an egg to appear eventually. Similar to the one on our recent pictures of the car. Interestingly, that was recently presented for an MOT test . In our Halifax tyre depot. Needless to say that if you have a  lump on your tyres anywhere. Importantly, then the tyre must be replaced as soon as possible.

 Eric Roberts

Hi I would like to introduce myself. Working in the Garage and tyre and Battery business now for 40 years. So. Working for a couple of national tyre companies before starting my first business. Of course, I now own a company here in the UK called Pellon Tyre and Auto-centre. Blogging about anything to do with cars and their related products. Naturally, that will help my business. We are members of Point-S and Trading Standards and are also a Unipart Car Care Centre.