Frequently asked questions on vintage tyres
What is a beaded edge tyre?
Beaded edge tyres were the first tyres to be mounted on a large amount of cars. The beaded edge had to be properly hooked into the rim of the wheels. Mounting the tyres was complicated and also dangerous because the air pressure had to be very high. If the edge is not correctly hooked into the rim, the tube can burst and cause serious injuries. The correct tyre size depends on the circumference of the inner wheel rim. The measurements display the external tyre diameter and the cross section of the tyre, for example 26 x 3 or 730 x 130.
What is a cross ply tyre?
The cross ply tyre was invented in the 1920s and marked the end of the beaded edge tyre which was used until then. The advantages of this tyre were a lower accident risk and easier mounting of the tyres. Polystyrene plies were used for the first time - hence the name. These were worked into the tyre diagonally. At first the tyres were mounted using a tube. Not until the end of the 50s was it possible to mount the tyres without a tube by using an inliner in the tyre in connection with a hump rim. The measurement was still in inches, for example 5.60-15 or 5.50-18.
What is a straightside tyre?
The straightside tyre was invented at the same time as the beaded edge tyre and was most commonly used in the USA. This tyre had no need for a surrounding beaded edge. However, this principle did not catch on in Europe.
What is a radial ply tyre?
The radial ply tyre, also known as the steel belt tyre is the latest development in tyres until now. The Michelin brothers patented the steel belt tyre in 1946. This tyre is made with a radial fabric carcass, ie. at a right angle to the direction of travel. This innovation had a positive effect and became standard in the 70s. The radial construction also made it possible to lower the tyre profile to 82% (the relationship between tyre sidewall height and road tread). This noticeably increased the cornering effect and thus also the safety. Through constant improvement of the chassis frame, the tyre profile could later be reduced more and more without reducing travel comfort. Today the normal profile is 30%. Tyres are measured in millimetres, for example 165R15 or 205/70R15
How do I know which tyre fits my vintage car?
As with a modern car, you find the correct tyre measurements for your vintage car in the vehicle documents. If no such documents exist you might find something by reading up on the subject. You are also welcome to ask us such questions. We have papers for almost every vehicle - and if not then we will find out the necessary information.
What does the writing on my tyre mean?
There is a whole lot of information on the tyre flanks. You are informed about size, load, maximum air pressure and the age of the tyre.
The measurements may look like the following: 205/70R15 90 W. When broken down this means:
- Tread width 205 mm.
- Profile 70% (and not 70 mm, as is often assumed) in relationship to the tread.
- Wheel rim diameter 15 inches.
- The "R" stands for radial construction.
- The "90" refers to the load and can be deciphered using a table in Kilograms (in this case 90 = 600 kg).
- "W" stands for the speed limit (in this case "W" = 270 km/h).
- For diagonal tyres all measurements are in inches, for example 5.60-15 P.
Here even the tyre width is given only in inches. A low profile did not yet exist.
Can I mount any old tyre on my vintage car?
Even vintage cars must respect the highway code. This means that all attached parts must be registered in the vehicle documents. From a technical point of view it is also important to mount the correct tyres as these affect both travel safety and -comfort. The gear ratio and speetometer are adjusted to match the tyres.
Can I reuse the old tubes?
As a matter of principle it is adviseable to use a new tube in a new tyre. A used tube shows pressure marks from the previous tyre. These marks will later become weak points which can lead to a sudden loss of pressure that could completely destroy the new tyre.
What is a tyre flap?
Tyre flaps are used in spoke wheels for motorcycles and lorries to protect the tube from bumps in the rim base and especially from the nippels. A tyre flap is a rubber band which is placed in the rim base. Sometimes this flap is also necessary in riveted steel disc wheels. It is not necessary to change it every time you change the tyre but it should be well checked for faulty areas.
How can I see the age of my tyres?
All tyres that were made from 1980 onwards have a DOT number written on them (DOT = Department of transport). This number tells us the calendar week and the year in which the tyre was produced. In the 1980s and 1990s the DOT number consisted of three figures. The first two referred to the calendar week and the last one referred to the year. The 90s can also be recognised by the triangle after the last figure. From 2000 onwards the DOT number will have four figures.
When should a tyre be changed?
As a rule, when the tread depth is at the minimum 1.6 millimetres. Vintage cars included. However, vintage cars are not driven as often as modern cars. This means that your tyre can easily be ten years old and still have a tread that is like new. When you go for your MOT test, however, the tester won't pass you - and quite rightly so. The rubber ages, hardens and loses it's grip. Over the years cracks also form and these could cause a puncture.
How long do tyres last?
This depends on various factors. A modern summer tyre can last an average of 5-6 years and reach between 40,000 and 50,000 km. However, it depends on driving style, power output, car weight and environment. The ageing of vintage car tyres is primarily due to environmental influences and the natural drying out of the rubber. As a rule you should consider changing your tyres after aprox. 10 years.
How wide should the white sidewall be for my vintage car?
The width of the white sidewall depends on the year that the car was built. Cars dating from before the war and up to the 1950s had a wide white sidewall. From the beginning of the 1960s a narrow, almost sporty-looking one became popular.
How are white sidewall tyres made?
Original white sidewall tyres are made by placing a piece of white rubber of desired width into the tyre mould and vulcanising it in during the production phase. In this way the white rubber reaches the tyre carcass. Another possibility is to vulcansie it on to the finished tyre after production. This makes it possible to equip modern cars with white sidewall tyres too. Of course the tyre profile must be at least 55%.