20/09/2017
So how do you ensure that your tyres are good to go? Here’s a simple trick to ensure you stay legal.
The 20p Trick
Use the 20p trick. Grab one and put it into the central tread groove of the tyre on your car. Repeat this for each tyre. If the inner ridge of the coin’s rim can be seen above the tread, your tyre’s under the limit. Get it changed as soon as possible or risk a fine, points on your license – and possibly worse. Drivers should really conduct the 20p test every month to check tyre tread depth.
What is the legal tyre tread depth?
The law states the minimum legal tyre tread depth for cars in the UK and Europe is 1.6mm across the central three-quarters of the tyre. The tread must meet this minimum requirement across its complete circumference.
But remember, this is the minimum. Many tyre and safety experts believe that this 1.6mm legal minimum is not enough to guarantee safety. In fact, they recommend a minimum tread depth of 3mm for tyre replacement. Tests by UK technical organisation MIRA found that, once tyres are below 3mm, stopping distances increase dramatically.
This is particularly significant when driving in the wet. The difference in wet braking distance between a tyre worn to 3mm and one worn to 1.6mm can be as much as 44%.
This is because in the wet a tyre’s tread helps disperse water away from the contact patch between tyre and road. If there’s less tread depth, less water can be shifted, increasing the risk of aquaplaning and losing grip.
In heavy rain, each tyre can shift one gallon of water every second, illustrating just how important depth of tread is.
Simply put, the deeper the tread the better the grip.
Tyre tread wear indicators
You can use one of these to check your tread depth. If the tyre is flush with the indicator, it is below the legal limit and needs replacing.
Tyre tread depth gauge
Another way to measure tread depth is with a depth gauge. This is a purpose made tool that quickly measures the depth of an individual tyre groove.
What do you use? Join in the discussion on LinkedIn and Twitter.