New Tyres vs. Just Legal Ones
JThe law in the United Kingdom requires tyres to have a minimum of 1.6mm of tread depth across the central three quarters of the tyre and have that around the entire outer circumference. This is an irritation for some road users and an absolute life saver for others!
Contrary to popular belief, it is not the tread itself that provides the grip on the road, but the rubber that is in contact with the road. In general, the more rubber that you have in contact with the road the more grip you have, therefore pretty much bald tyres will then provide the best grip.
So why then is there a minimum tread depth at all?
Everything stated so far about grip and tread depth has really been talking about dry road conditions. Driving in we weather conditions is a completely different story. The reason for tyre tread is simply to disperse water. The tread simply channels the water away from the road-tyre contact. If there is no tyre tread, the water would effectively be pushed along in front of the tyre reducing adhesion with the road.
In some European countries there is a minimum legal tread depth of 3mm as opposed to 1.6 in the England. The difference in stopping distance between 1.6 and 3mm is actually quite significant according to many experts.
So, finance permitting, it is a sterling idea to try to change your tyres at 3mm as opposed to the UK minimum. While driving in the wet, your life could really depend on it!
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